The Merkava IIA, as discussed, is the obvious go-to for complaints. It's already been covered, but you're basically buying an M1IP, but you also get BMPT-like anti-infantry and stun capability built in without the BMPT's inability to deal with heavy armor. It's easily 5-15 points too cheap.
To throw an odd one out here, what about the supply cost of the MAR-290?
(I'm assuming the supply cost listed in the mod tools are for a full reload, not per-shot, otherwise the situation is waaaay crazier)
TL;DR - The MAR-290 is an Urugan with +50% ROF and -22% supply consumption for just +12.5% cost. Increase resupply cost to 400.
Eye-burning wall of text spoilered for sanity:
60 HE, splash 9048, dispersion 3640m
266 supply, 120s reload
Urugan (120 points, 2 at trained or 1 at veteran)
176 HE, splash 6864, dispersion 4550m
1008 supply, 180s reload
Now, I don't know the damage dropoff formula- and would love to learn it. This could change things. However, let's just assume it's linear for now and if someone wants to explain how it really works we all learn something.
Area increases with radius or diameter squared. So, working with those values:
MAR-290 damage density = 370 = ((60 * 9048 * 9048) / (3640 * 3640))
Urugan damage density = 400 = ((176 * 6864 * 6864) / (4550 * 4550))
So, the Urugan's a bit better boom per area. It's also longer ranged, which also means it'll get better range scaling, and it's nuking a noticeably larger area. For a single unit and disregarding supply, that sounds pretty good...
... except you can buy 50% more MARS 290 units, firing 50% faster (3 shots in the time an Urugan takes 2), using only 26% the supply per shot.
Work out all the numbers and what you get is the MARS 290 is an Urugan with finer control over the placement, +50% ROF, and -22% supply consumption, for +12.5% cost.
Easy fix, however. Just increase the supply cost to 400. Now its supply consumption is pretty similar to the Urugan's. The Urugan offers you better damage density (because it's longer range == more range scaling), the MAR 290 offers you finer control over your shot placement and +50% ROF.