Flak/artillery

Stationary units that can only be moved once which have a range of attack but do not move?

Could strengthen defensive lines as well

Dito, but just to say, they would be more fun if movable by transports.

This may make a need for an IVF/APC/'Land' Transport. I think such units for moving infantry would be welcome regardles, as infantries' main weakness is that they are fairly slow.

Maybe if it took more time for them to move than normal units it would be an easier fix than creating two new units.