Units such as catapults can now make ranged attacks, but can not make "direct" attacks. They can still bombard.
I think on balance this makes them stronger than in BTS. Therefore, I think they should cost more to build.
Now, if you are on the attack, usually you should lose very few if any of your catapults, cannons, etc. As your army moves from battle to battle, as long as you are strong enough to survive, there is little need to replace lost catapults, cannons, etc.
I personally think that having the capability to both bombard and do ranged attacks with collateral damage is too much for a unit like the catapult. I have no problem with this for artillery. I think you need to somehow tone down the early units such as the catapult and trebuchet. Perhaps allow one of them to bombard and the other to do ranged attacks, but not both. (I hesitate to get rid of collateral damage since that is in there for a game purpose.)