I can say that faster ships would be more fun, but that's from a pilot perspective; and of course you don't want them going -too- fast, which is what I think most people are worried about.
By increasing ship speeds, you will change the balance of the game. That's not to say it will imbalance the game, but things will definitely be different. We can always adjust other things to compensate, but that's a pretty large effort; and you have to ask if changing all/most other aspects of the game is worth the change? Faster ships would be more difficult to hit. Do we reduce the hp of components? Would tools make the ships be way to maneuverable and have to reduce their effect? Would tools still provide enough of a difference to be useful, or would players switch to utility tools instead of maneuverability tools? Would we need to increase gun arcs and shell velocities? Would the ship masses need to be adjusted so ramming doesn't do crazy huge amounts of damage from the velocity? What about the really slow ships or guns with small arcs, would they even be competitive anymore? Would the small maps be too small now?
Increasing the ship speed would increase the skill cap for gunners, and probably pilots, but likely reduces it for engineers. Faster movement means you need better reaction times and coordination, because things are changing at a faster pace. With ships moving faster, you need to be able to lead them a lot better -and- compensate for your own ship movement more. Now with shots being harder to land, and ships having an easier time getting out of arcs, this ideally gives engineers less to do. Sure there's always going to be repairs, but there's no 'you need to get this exactly right or we're dead', since there's a higher chance of error on the pilot and gunner level.
Or perhaps engineers will have to do better, with their pilots more likely to smack into obstacles and enemies able to suddenly appear and hit you hard. Engineering will probably be about the same really.
Right now pilots are less about flying skill, and more about decision making and strategy. Once you're in a situation, there's not a whole lot you can do to change that. If the enemy sneaks up on you with a metamidion, you can hydro, vent, phoenix claw, etc; but mostly it's "Oh, guess we're dead now." Because any movement you make isn't fast or dramatic enough to throw them off enough to spare you. You need to be prepared ahead of time for that kind of event, and no amount of skill will save you (most of the time).