Riot games have put a special effort into having balanced champions for this game style as well. I don't believe there are any champions to avoid. However, the team composition changes a bit.
AP Carry
You will still need one, or else the other team will just build against AD and will own you as soon as they are a bit stuffed.
Tank / Off Tank
King in solo holding the bot lane, also very good in "tower diving" (if we can still call it so in Dominion).
Melee Fighters
They tend to be the heroes everyone picks as they are sort of kings on this map. They deal quite some damage and have high sustainability (so they don't need to Back often), and are often very good in 1v1 (which happens pretty often in Dominion).
Ranged AD Carry
More than one is too much, but not having one (to have more fighters) is a handicap. He deals crazy damage and can attack out of tower range or defend minion waves without exposing himself in front of the tower. From the games I've played or seen, having only melee champs is clearly a handicap.
Support
I rarely see them in Dominion and believe they are overlooked. Each time I've had one on my team, it was awesome to hold the windmill (we never had to back, support would always buff/heal us).
However, having a support requires good team play, because the champion won't do anything on its own (compared to fighters).
General
As XP gain is so fast in Dominion, teams are usually built with mid/late game champions. Riot tried to correct this in a previous patch by lowering the XP gain aura on the map, however, you still get to level 6 tremendously fast, so don't hesitate in taking weak early game champs (like Kassadin, useless before level 6).
Try having a hero or 2 (at least) with high mobility (Rammus, Kassadin, Nocturne, Twisted Fate, etc.) to do lane swaps and be unpredictable in your tower attacks.
Conclusion
All heroes are viable. It all depends on the team composition.
Good Akali, Irelia and Xin Zhao champions can however be freaking awesome with their ganking abilities and life steal.
So your basic question seems to be: Surge or Promote?
This is a rather strange question as those two summoner spells fit very differently into the current Meta-game. In fact, I don't believe there is ever a hero I could imagine having to choose between those particular spells as they serve very different roles. So instead, let's assume that you want to know when these two spells are appropriate (and not make a choice between them).
Surge
Surge is a rather recent introduction into LoL and is still having its place in the meta-game examined. While it does act as a much needed steroid for a number of champions missing one (eg. Twisted Fate or Teemo), it suffers on champions who require a lot of farm (i.e. most carries). In comparison to spells like Ignite and Exhaust, Surge (while scaling better) just doesn't guarantee kills the same way through early/mid-game. Now, it's true that Dominion has a shortened early/mid-game, but it's just as true that it has a shortened late game (where this spell really shines). As a result Surge is frequently not the best choice for champions (even carries).
Promote
Promote is another spell which hasn't yet found a good place in the overall meta. However, having been around longer, there are more obvious cases where people use it (i.e. in Dominion going bottom against a Champ who has trouble clearing lanes early on, like Tryndamere or Yorick). Given Promote's role in taking down towers, it's no real surprise you see it more often in Dominion than Summoner's Rift. Usually, you want Promote to push your creep wave into a tower allowing for a better engagement at a node. This frequently means you find Promote on Champions who have trouble clearing lanes or who are good initiators. A Champion that requires more farm or is main DPS (i.e. a carry) is a less likely place to find promote as it doesn't fit their role well.
Garrison
I'm surprised you're reading a lot of information that Garrison is a poor choice; it is quite a good spell. The problem with Garrison is that it really only shines is defending nodes in Dominion. Very frequently people don't do this (usually because it's less exciting). However, there are a large number of places where your team can really benefit from Garrison (solo bot, or even defending top). Garrison can break a channel (from further range), stop a wave push, or even heal a node, all very useful things in Dominion. Even if it only forces the other team to break off an engagement then it is directly translating into victory points (something few other spells do).
When to get it? When you're running a 3 Node defensive strategy or against a team with a lot of floaters (e.g. Rammus)
When to avoid? When you're filling a more important role (i.e. Carry) or you're going for a more aggressive strategy (i.e. running floaters)
Flash vs Ghost
Both of these are excellent spells (and there are even times when you might get both), but in Summoner's Rift, at least, the current meta-game has stabilized on Flash being invaluable. This is largely due to two factors:
- Flash lets you get out of (or into) range of abilities and champions
- Flash lets you "jump" over the twisting terrain in SR
However, in Dominion both of these reasons are less effective. The terrain in the Crystal Scar has fewer features you can "jump" with Flash, the faster game play means champion deaths are less impactful (thus saving, less important). While still a great spell, Flash is nowhere as dominant in the Crystal Scar as it is in Summoner's Rift. Instead, two other features dominate The Crystal Scar which make Ghost a frequently more picked spell:
- Non-linear attack routes
- Contested towers
Having multiple paths to engage (and less vision) often means you are forced to move to positions very quickly. This is the reason champions like Rammus are so frequently banned. What's more, it's frequently a strategy to rush to the top tower at the opening of the game to assert the defender's advantage. In a rush strategy (fairly common) it is necessary that most of the top defenders have Ghost to out pace the other team. As a result Ghost may not enjoy the same dominance that Flash has in SR, but is still a powerful spell (and a frequent choice).
When to get it? Both Flash and Ghost can be great spells on any Champion
When to avoid? Only when you have something which is much higher priority or more synergistic with your strategy (like Zombie Karthas was).
Best Answer
TL DR:
Against turrets:
Against minions:
Full answer
Not really. It can be quite complex.
Minions get a different bonus from baron and promote based on whether they are melee, casters, or cannons. To check which one deals more damage per second (dps) we will ignore how long they survive (obviously a ranged cannon would take less damage from enemies than a melee minion).
To do so, we multiply their total attack damage by their final attack speed. Then we apply multiplicative bonuses. Minions deal bonus damage to towers, and have a penalty on champions (but champions aren't examined in this answer).
Any damage reductions (e.g. armor, magic resist, etc) are disregarded, so dps values below are unmitigated. Lastly, game time is set to 30.
The results are:
This is the Python 3.4 code I wrote and used for above results:
Although i did check some of the results (and they seemed reasonable) I have not tested everything. In case you find a mistake, please let me know.