3 possably solutions to this
A) a simple adition to the rules could be all ships must be moved forward in direction of facing thier size in " befor taking each action.
so for example my challenger example would have to move 4" befor its 1st action say ready (turn) then just befor second action it would move another 4" and could shoot or move with its second action or turn around again.. efectivly staying still at the exspense of shooting.
B) a ship must move its size in " after its first action, unless ship takes a ready action to apply stationary thrusters. this move must be in direction of facing.
C) a ship must move its size in " befor its first action, . this move must be in direction of facing.
D) ships must be moved forward in direction of facing thier size in " after taking each action.
it the challengers 1st action would be to shoot, then its forced to move 4" second action could be to turn then it would be forced to move another 4"
i like the fun and pressure A) could add, i like the trade of on version B) and version C) seems most easy to manage, and finaly jsut edited in is D) wich worked very nicly as it gives you a chance to change heading befor being sent of the table, also D and A allow a ship with a ready action to cover a distance of 4+4+14= 22" i ansty suprise for the enemy or a great way to make distance and try to escape or change your flank attack.
im siding for D) as its easiest to remeber and use in a game from fidling with modles,
I'd have to say D as the best. If the
Capital Ship trait means you move your a distance equal to your size forwards after each action, then you have to deal with 6-8" of compulsory move - it also adds in a certain amount of issues with timing; you have to fire with your first action before movement carries you out of range.....
Equally, it means that you don't actually have to 'move' - simply rotate (and free move) or shoot (and free move) - actually making a move action therefore represents gunning it and trying to push beyond normal 'cruising speed'. I'm not sure that a
Wheels or
Tracks equivalent is necessarily needed on top of that.
Also, I'd cut the move distances down - if a challenger main battle destroyer is getting 8" 'free' move, then its actual move actions don't want to add up to more than that - 16" move is about the most you want to have a unit moving on a normal sized board.
Although a very long distance one (i.e. more than the usual "two move actions plus an inch or so") makes for a nice in-system hyperspace jump. You can even use the trait name
Jump for it - since that does exactly that... As you noted, one ready action for warming up the jump engine (plus a short drift) and then a jump of a foot or so, a free shot, and another drift. It's kind of akin to a 40k turbo-boosting bike; but also has a nice effect (due to the EVO rules) that since you can react to any action when close enough, you may find yourself getting shot at when making the ready action ("Hit them before their jump engines are charged!")
I do like the effect that a bigger ship has more inertia to deal with. The downsides are that:
(a) it also makes a bigger ship faster unless the smaller ship uses move actions to keep up, which gives it even less chance to use its already inferior guns.
(b) a command ship's extra action makes a ship suffer more from inertia by using its ability. Equally, nothing forces you to use both or even any actions with a given unit, which dismisses inertia at the same time in this model.
(c) it kind of stymies the idea about turning close combat into close-ranged weapons, since the size area - effectively the range of those guns - can't be more than about 4-5" radius or the inertial movement becomes ridiculous. I do think that close combat is a good way to deal with fighters - an infantry model equivalent making a charge action is equivalent to a strafing run, and a bomber can use an actual ranged weapon to fire from a longer range - so it doesn't expose itself to a charge action in response from the enemy capital ship, where the flak weapons would squash it flat.
I think (a) and (c) are fairly easily dealt with by making the inertial move a fixed amount as part of the
Capital Ship trait - enough to make it impossible to hold position and to allow people to position themselves to take advantage of it, but not enough to turn every ship into a drag racer. I'd suggest 3" (bear in mind that this will be doubled up to 6"). With that added to the straight-line speed of every move action, it's going add up fast.
(b) requires a couple of extra provisions; firstly the
Capital Ship trait could use an additional provision that you MUST use both actions each turn (but obviously you can waste them with a ready action with no practical effect if you wish). Although (that said), I suppose it does give you the ability to 'all stop' by essentially shutting the ship down (except for reaction fire).
Secondly on (b) the
Command Ship trait needs a provision that this additional action does not require a unit with the
Capital Ship trait to move after completing it.