Was about to go with the obvious 'spawn more swarmers/allow all factions of swarmer' abilities that have been suggested in the future card ideas thread multiple times, but I thought I should try and think of something else, not that there's anything wrong with those abilities.
Seeing as there's no overseers swarmer yet...
cost 6/morale 8
When Ascending Swarmer is on the battlefield all insectoids you control have Flying.
If you control 8 or more insectoids Ascending Swarmer ascends.
While ascended, Ascending Swarmer and insectoids next to Ascending Swarmer have +2/+2.
I dunno about it in terms of balance, just wanted it to be like overseers in terms of trying to get a bunch of units out and rushing with flyers, not too sure about the ascend ability, I was just trying to think of an 'ascended' effect that wasn't just a copy of one of the pre-existing angels.