EIRR games consist of teams, not just one player.. the bigger the game gets, the harder Maus/JTs get to take down or cap around. The sheer amount of AT it takes to kill a Maus is absolutely ridiculous, making the maus extremely effective in whiddling down an allied team's AT with little effort. The jagdtiger on the other hand is just plain stupid. The AVRE was "rebalanced" so that it wouldn't gank squads, so that EIRR would keep its persistency, yet the JT is able to one shot squads with ease, has no cooldown, far more HP, better armor, and requires FAR less skill. Infantry squads have absolutely zero hope of dodging a JT shot due to the ridiculous AoE damage it does. ATGs being one of the primary counters do jack against a jagdtiger due to the fact that it can drive up and one shot it taking little damage at all.
Jagdtigers especially ruin the balance and fun of any game. Its like a heavily armored, mobile, howitzer that auto targets and rapes everything in its path with no decent counter. A jagdtiger + storm shrecks/paks literally has no reasonable counter in a game and needs to be toned down considerably if this unit is to continue being in play. I realize this isn't the only overpowered reward unit, but it certainly seems to be one of the worst offenders.
While I will agree that the larger games inherently make these super heavies harder to combat, that in its self is an advantage due to the sheer number of extra counters you can have like
RE smoke screen plus stickies
Button plus 17pdr-76 mm atgs
Ameri mgs + jeep + firefly
Button plus lancaster bomb
Mines spam + mines spam
Airburst + zooks or rrs or piats
A bit of theory craft yes but most of them worked for me during the "reward test phase"