The most important thing to consider is what your army can do if the lynchpin were to fall. this list hasn't got target saturation, armour saturation or that much offensive potential. if a flier arrives, you're almost screwed. if 2 arrive, you are screwed.
Big guns are static, so if you play on a decent board with line of sight blocking terrain (makes games infinitely more fun) then they'll have to be deployed to maximise their area of effect but cannot threaten the whole board. the stompa will act as a bullet magnet for every piece of anti-tank in the enemy army, and if you're facing eldar, space marines, necrons, orks, tau... ...scratch that. If you're
not playing tyranids or daemons then it'll be coming down pretty fast. the buggies and skorchas are only AV10 so people will divers small-arms fire onto them to glance them apart, and your lack of infantry will only remove their decision making in this field.
even if you came up against a savvy player who didn't have a balanced quantity of anti-tank, they can simply outplay an army like this using objective secured and multiple small units.
sorry, but I don't rate this list myself.
though that said, if stompas can still carry several units, you could put the grots in the stompa and chuck them out at strategic points as you walk across the map. putting your only objective secured units in vehicles that won't move more than 6" a turn (unless they roll a 1) isn't going to get them anywhere. you'll be striving for the good shots, not speeding to the objectives.
by all means try it, but I wouldn't expect it to do well against a balanced or objective-themed list. I prove this in
This Battle report.
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