Just like chemical and biological weapons,IMO some are seeking a solution to a non-existent problem. This is a tactical scale wargame.
If it ain't broke, don't fix it. With FAE's,cluster bombs and MLRS artillery,SPMBT can rain immense amounts of death and destruction on an opponent as it is presently designed,and that is "enough" for this long time advocate of the Steel Panthers series.
The beauty of this wargame is it is totally customisable. If one needs an "overkill" fix,pit the 1946 Red Army against the USAEUR forces from mid 70's. M60 tanks and M551A1 Sheridans can make short work of the enemy,even being out-number 5 to 1,and especially when backed up by an 8 inch howitzer battalion and a Cav squadron 155 howitzer battery.
p.s. I think we in the 2/11 ACR could have done a pretty good job in reality as well against the T-62 and T-55 tanks that faced us on the other side of the fence in the Meinegen gap region of Germany in 1974.