To start with, this game is nothing like UT. It's beta, so there's things to be fixed of course, but besides some performance quirks there's nothing game-breaking here.
Visually, the game is pretty solid. It looks and feels great. The beta currently seems to be lacking some audio cues, but it also seems to sound pretty good to. The gameplay is fairly mediocre though - it plays much like a regular shooter with some heavy camera animation and a 3D HUD. In many ways it feels like a clunky, watered down UT. It seems to be lacking in a lot of variation, so I can see it getting old very quickly. The default controls are painful (shift+direction to dodge), but thankfully you can define this as a double tap and rebind the awkward keys.
If you want variation try switching up your primary weapons. You unlock new ones at certain mech-levels free-of-charge. I found that shift-dodge is more effective than double-tap for me, but that's player preference of course. Don't forget about the quick-turn (Shift+S or double-tap S.) If you're suddenly getting attacked from behind or you need to flee combat, using this effectively can turn the tide of the battle.
Unfortunately for Hawken, there are two key problems I've identified already, and they seem to stem from the Freemium mechanics. You start with no XP and no credits, and there are two temporarily unlocked mech classes you can play with (and the 'Recruit' mech class is always available but has weak stats). Each mech class levels up individually based on XP earned by playing, which also nets you credits. This part is fine in itself, but it gets convoluted and problems start from here. Each temporary class is available for one month, and then gets rotated out and you lose your progress with that mech unless you have it unlocked permanently.
Okay, the different mech classes all come down to play style and preferred strategy, not pay2win. None of them are really more powerful than the others. Some of them have unique abilities that can aid you in offense or defense, and some can dish out more damage per second but then require a longer cooldown period (at which point the Recruit's primary weapon is still humming along at you.)
Also, the starter Recruit mech is a perfectly good all-around mech. It's a match-winner if you learn how to use it and you employ rudimentary battlefield strategy.
As for the temporary mechs and their level progress, see my argument on that further down.
Mech classes take around 6-8000 credits to unlock. I suspect it will take in the region of 80 hours of play to unlock a mech class. Each game also earns you XP, which slowly levels up your mech. I have currently only reached level 1 in my two hours of play.
I have only been playing for about fifteen hours and I have somewhere in the neighborhood of 2,500 in-game currency and my Recruit mech is level 18 or 19. I was at least level five after two hours of play. I average somewhere between 2,500-3,500 experience per match because I do a ton of damage and get lots of assists. I have already unlocked a lot of the first and second optimization tiers for that mech as well as some of the items that go into the internal upgrade slots.
If you've only gained one level in two hours of play, you're doing it very wrong. You gain experience and rank by causing damage; kill/death ratio isn't actually a factor. Don't go for the quick kill every time, just keep your aim as steady as you can and dish out as much damage as you can. Even if your opponent kills you, you'll get experience for that damage when someone else tags him in the form of an Assist.
Each mech has a number of upgrade slots, each with a number of options; superior primary and secondary weapons, and differing offensive and defensive upgrades. These also each cost a few hundred to a couple of thousand credits to obtain dependent on what they are.
Again, most of these items unlock free based on mech level. None of the primary weapons are really any better than the others. It depends on your strategy; if you often find yourself fighting up-close and personal, go for the sub-machine cannon. If you're a mid-range guy, go for the assault rifle. If you're somewhere in between, go for the vulcan cannon. Otherwise, their specs are very similar.
Some mechs have other types of primary weapons, i.e. flak cannons, sniper rifles, missile pods, etc. But in combat, they're not really any better than your assault rifle. It all comes down to player strategy and learning how to time and dodge the opponent's attack.
You have to however reach a certain level to unlock those options in order to buy them (there are even "prestige weapons" for high level players). Lastly, and this is the part that sucks - each level you gain on your mech class allows you to choose from an upgrade tree; allowing you things such as extra weapon damage, extra movement speed, better cooldown rates etc. This means that players who have leveled up their mechs will have a statistical advantage over those that have not, and will have access to better weapons and alternative equipment - something which is easily observed by playing the game since the game does not match make according to player level or experience. A level 20 mech will have chosen 20 more stat upgrades than a level 0; and have access to weapons that are not really different, just superior :/
Again, this isn't even a big deal. Tons of other FPS games do this. If they have upgrades, you need to adapt. Employ strategy, learn to use shields, and learn to use the repair function. Even when I was level three or four I was easily beating level-20+ heavy-armor mechs with missile pods. It's all about dodging their attacks as best you can while effectively using TOW missiles, or sneaking up behind them to get the first strike (TOW missiles in the back do a LOT of damage.)
Also, optimizations don't even improve mech stats by a whole lot. They can give you a small edge in combat but only if properly used. Most people don't.
As for the different types of primary weapons, I already covered those. They're not more powerful, you just need to learn how to deal with them. If the other guy has the SMG, then get some distance on him to reduce his accuracy and pound away with your AR and TOW missiles. If he has the vulcan, a good strategy is to try to get on his side or behind him where he can't get a target lock on you, because the vulcan overheats quickly.
Don't forget that your Recruit mech also has a special ability that offsets heat; hit F when your weapons are close to overheat to keep firing.
