As has been talked about before things like more choices other than the 'No Artillary','Infantry Only',or 'All Vehicles' should be added i think.
I think you could add say options like 'Light','Medium' & 'Heavy tanks' only.
But make it so you could have a combination of all of those,ie,light & heavy or medium & light tanks or medium & heavy,that would solve the problem of only using tanks for particular times of the war as during the war most tanks started off light then medium then heavy for all sides.
For instance at the beginning of ww2 panzer i's,ii's were light tanks,panzer iii's medium & panzer iv's heavy tanks,but by the wars last months panzer's i + ii+iii's were discontinued,panzer iv's & v's were medium tanks & panzer vi's were heavy.
So that being the case options for Light tanks & Medium Tanks only or Medium Tanks & Heavy Tanks only would be best thing i think.
Of course that would also include Self Propelled Guns or Artillary to.
P.S.I played an infantry only 8*8 game last night & although fun it was kinda overrun with people on both sides buying loads of Heavy MG's,my point being might be a good idea to have the option to turn off those or mortors or guns on the infantry only modes.