This is a question of character knowledge versus player knowledge.
Cryptanalysis is a fun, if little used, human skill. Some players will delight in solving cryptographic puzzles, and 4e certainly doesn't prohibit the gamist approach of "challenge the player."
On the other hand, cryptanalysis is highly binary. People either really like it, or basically can't stand it, especially if you start branching out into some of the more interesting, but trivially solved cyphers (playfair, Vigenère).
I, unfortunately, had to learn this fact the hard way. Players, as a rule, will take one of two approaches to puzzles. The first approach I learned when I gave a cryptogram in a sci-fi game: "I hire an expert from town to solve it for me." is the general pattern here. To make this approach interesting, the cryptanalysis must have extrinsic complications such that one can't submit it to an analyst (magical or otherwise) and wait it out. Beyond that, having a player go "and I solve it. what does it say?" is absolutely valid, and should require either a pure int check, or a skill check of an appropriate skill the player is bringing to bear. I would personally recommend looking at the serious skills series to see how to make this approach more interesting, as players can add depth to their character by describing how a particular facet of knowledge was brought into play. Still, if you're not expecting it, it comes as a horrible horrible surprise. Some people just don't find puzzles fun.
For the players who find puzzles fun, especially for a 4e game, take a page from Portal.
Teach players one component at a time of the puzzle. It'll seem way too easy to you, but you know the context. For a crypto puzzle, start by teaching the alphabet. (Maybe touch the "true characters" not to get shocked) In subsequent challenges, teach the order of the alphabet. Again, always give an example of what you're looking for before you ask for what you're looking for. (Or, provide a way for rapid abductive reasoning without penalty.)
This way, after quite a few sessions, your players will be able to manipulate the language as a tool to solve problems, and may occasionally be assisted by their characters-as-characters.
An interesting touch would be to make the language three dimensional, and have the puzzles follow the rules of the game Zendo. Then the rough series of questions can be "complete this sentence." or "find the incorrect thing." Both are completely appropriate to solving a crypto-language, and both can engage players, instead of abstracting the puzzle to their characters.
It sounds like you're over-using the 'hits the guy who triggers the trap, no reset' variety of trap. There are a lot of other, more exciting traps you and your players may find interesting:
'does something insidious but not immediately apparent, no reset'
- When the players press this pressure plate, the ceiling of the entrance corridor to the dungeon seals shut, trapping the players inside. It will not reopen for 3 weeks, and if more than 10% of the stone is excavated it will not reopen at all. Hope your party brought supplies!
- 10 minutes after this ward is breached, this section of the dungeon begins filling with (choose one: water, sand), which pours in via a mystic portal to the Plane of (Water, Fire). The substance continues to pour in until the body of material reaches the vaulted ceiling of this room, blocking access to the portal and causing it to shut off. If the material is somehow diverted, the portal closes 10 minutes after activating. The portal can transport up to 3 10' cubes worth of material per round.
- Once this tripwire is triggered, an alarm is triggered far off in area 3, alerting the bugbears to the presence of intruders and allowing them to rouse their companions and prepare an ambush.
'does something obvious, but resets and continues to pose a potential threat'
- This pressure plate triggers an arrow trap that fires down the corridor. The arrow trap is set to automatically reset each round, and holds a reservoir of 500 arrows (worth 12.5 gp if the party empties the container by triggering it and salvages the arrows). If the hobgoblins fight in this hallway, they attempt to form lines so the PCs closing with them will be forced to trigger the arrow trap.
- This door is infested with Ear Seekers. Anyone touching the door transfers one of the foul creatures to their clothing on a failed reflex save (90% chance if the infestation is unnoticed by the party), and anyone attempting to listen at it is automatically affected.
- When the ward is breached, the warded area appears to fill with whirling darkness and a piercing shriek can be heard. Under the cover of darkness, a set of scything blade traps attack everything within 10' of the center of the room. The darkness and shrieking is illusory, but the scything blades are real. The blades retract as soon as the room is unoccupied, at which point the darkness appears to drain back as if through a portal. The wards trigger again if any creature again enters the room.
'does something insidious, continues to pose a hazard'
- This "pressure plate" is actually a rather intelligent mimic sitting in a floor cache that contains the level used to open the secret door to area 4. If the party presses the plate remotely or appears too difficult a fight, the mimic pulls the lever and opens the door. If the party appears weak, a single character attempts to pass through on their own, or the party has brought pack animals, the mimic attacks, first using its control of the secret door to isolate its victim or victims from help.
- This bookshelf contains a translated copy of the ancient play 'The King in Yellow'. Any character reading the first act of the play finds it quite mundane but vaguely unsettling, but anyone reading even a word of the second act feels compelled to ensure the play is performed. This functions as a Suggestion spell cast with a 9th level slot except that it is a 9th level effect, functions even on creatures incapable of being charmed (though they possess advantage on the saving throw), lasts until the creature witnesses a full performance of the play, and can be removed only by Wish, Greater Restoration, Heal, or Dispel Evil and Good cast with the additional verbal component of the long-lost name of the eponymous king, thrice spoken. Warlocks with the Thought Shield feature are immune to the book's effects
Lastly, you can always use traps that hit someone other than the person triggering them, for example casting fireball or filling an area with toxic gas or otherwise generating an area effect, but that isn't terribly much different from what it sounds like you are doing now, and will just lead to players standing a little farther.
Best Answer
You cannot do better than follow the advice in the Angry GM article. In summary: have only one or two types of traps that are detectable by the players.
What the article does not address is using traps as battlefield obstacles which is the way armies use "traps" like landmines and barbed wire. These things do not stop enemy armies but they can channel movement - clearing minefields and barbed wire takes time. Either the enemy takes the time and you can redeploy to meet them as they come out of the minefield or they go around the minefield into an area already under your guns.
These types of traps are not "set and forget", minefields have to be patrolled or the enemy will lift your mines and use them against you as the Australian Army found out in Vietnam.
What works for armies can work in D&D. Intelligent monsters can use traps to delay or channel movement during an encounter. A fight with kobolds is easy, unless they know where the pit and arrow traps are and you don't - they can manoeuvre so the straight path to them takes you into a trap. Once this happens a couple of times your players will move around the battlefield with much more caution.