I have to agree with Penguin.
I never see Jesters used and I myself never use them because they are almost never worth it. If boosting the dps/mass is out of the question then maybe another method of making it more usable? What if the cost is reduced along with the maximum HP as well. That way it can be countered easier by T1 mobile AA. The whole point of niche units is to give different factions some flair. But if they are almost never used they might just as well be removed.
Using it as a defensive unit doesn't make sense because a t1 bomber is much more effective in that role. Bombers do area damage, cost less, and build faster. If the enemy player you're trying to defend against mixes some AA into their army then bombers will be much better because they will get at least one bomb off dealing damage to many targets where the Jester won't be able to deal nearly as much. If the player doesn't send AA the bomber would still be better because of the area damage and multiple passes.
For sniping early mexes the Jester is also inefficient. You can build about 5 T1 mexes for the price of one Jester. the reclaim from the destroyed Jesters alone will make up for the damage they deal.
The only concern I can understand thus far is the Comm snipes. However I constantly see people talk about wanting to punish players for poor/ lack of scouting. If the same mentality is applied then players should punished for poor AA defense as well. But I believe my original solution might still help. Cheaper Jesters with less HP will be easier to counter so it might balance out the Comm sniping potential.
Just my two cents