This answer is outdated as of the 2019 Commander Lilith DLC, as noted in this answer
The max level in the Borderlands 2 base game is 50, giving you 45 skill points to spend. Gearbox actually has a character planner on their website (which can be found here) that should help you pick out your skills.
Borderlands 2's "Ultimate Vault Hunter Upgrade Pack", available for $5 (or as part of the Season Pass DLC) can be purchased to increase the level cap from 50 to 61.
The Ultimate Vault Hunter Upgrade Pack 2: Digistruct Peak Challenge DLC further pushes the level cap to 72 for those who own it.
The best bosses to farm for items are BNK3R, Warrior and Terramorphous. You can't fast travel to these locations, so what you need to do is kill the boss, quit out of the game and then restart the game. The boss will be back and you'll be right at their front door instead of having to run the respective gauntlet before each boss.
Note that Orange/legendary drops are extremely rare except from certain bosses (even then orange drops are absurdly rare. Killed BNK3R 20 times this weekend and got squat). Farming is an effective way to get purple/blue weapons from any boss, but you'll need to target your farming if you want the legendaries.
Also note that Terra always spawns at level 52, so if you aren't level 50, don't bother. See also my guide on killing the crap out of Terramorphous. Similar to the advice in that question, The Bee is an effective way to farm any boss; it used to be insanely easy, now it's just significantly helpful. The Bee has been nerfed (more specifically Amp Shields in general) so the boost is less significant for multi-projectile weapons, so if you're using the Bee, try a single bullet per shot, high rate of fire weapon like a Spinigun instead of a shotgun.
BNK3R in particular is easy to farm for Assassins since the Bore skill is bugged for him and sometimes he'll take repeated hits from it (with increasing damage) and die in very few hits (or one).
However, regarding farming before playthrough 2...Don't farm before playthrough 2. Actually you need to be in playthrough 2.5 (e.g. complete playthrough 2) to get the best items possible. Don't farm until your level is maxed out; unlike Borderlands 1, damage follows an exponential scale in Borderlands 2. This means almost immediately after playthrough 1, orange level 30 guns are total crap compared to green level 35 guns. Ditto even up to level 45 guns. Everything is crap until you hit the level cap, just play normally until then and don't worry about farming.
Best Answer
Well, Close Enough bullets will always ricochet (at the % chance provided). If there's no target to home to, they bounce at the opposite angle of impact as you'd expect.
I'm bad at spitballing distances, but this is about the maximum range I could get ricocheted shots to hit enemies (confirmed by the blue numbers there)
That's about...what...50 feet? Note it's the distance from where I'm shooting to the targets, not from me, which is about halfway in.
So yeah, you do have to be reasonably close to the mark, but not quite "right at their feet". Pretty much as long as you're firing directly into combat it should work, but you can't just use it to long-distance snipe by intentionally missing; I bet that's by intention.
So you won't be hitting any surveyors with it; use Deathtrap for that, he's a doll. He also rips up buzzards.