I don't post very often but, as an AST main since 3.0, I must agree that the Balance card need to be tuned down.
This is just... not fun. The card is not fun to use, it's literally the most powerful card AND the laziest one to throw at your party.
Since 3.4, the gameplay of the Astrologian is all about Balance; I mean, even before, Balance was the best card but you could use other card without hearing your party ''Oh... Arrow... but, throw it away we want the true DMG buff".
I love the job for their RNG 6 cards buff, not for playing lottery to get an AoE Balance like it's a regular spell. I like feeling rewarded for good use of my buffS and not for ''Omg 5 AoE Balance in a row, I'm the best AST eveeeeer".
When you look at it, Bole is an indirect dps buff for healers ( and maybe tanks ), and it helps to save some MP since you'll need less healing, Spear is the hardest card to use well, Arrow is good on certain jobs and bad on others so you have to be careful, and Ewer/Spire cards need you to analyze who needs it the most in your party at any given time. And here, you have balance, throw it on your highest DPS and call it a day.
How many AST players since 3.0 still find our buffing job fun?
That being said : what are the solutions? Nerf Balance so cards will bring less DPS and our whole card system will feel weak(?), or nerf our healing but keep the boring Balance buff? None of these seems really fun to be honest
Now about the WHM state... I don't know, it need some mitigation and better MP management at least, but I agree that all healers feel balanced because they are all viable. Now, I think that if anything should be done, they need to balance them all at once, because SCH is still way too powerful, AST bring too much raid DPS, and WHM... well... nothing. You just can't nerf AST without touching SCH, the "meta" shouldn't be WHM/AST + SCH like before, no job should have a guaranteed place in a raid group. So yeah, better buff one healing job than nerf two in my opinion; but still : AST don't feel fun anymore, at least to me, so I hope they'll adress that in the future.
( I know efficiency > fun, but before 3.4 card system felt a bit more fun, and if only they buffed Arrow to match 10% balance and buffed/reworked Spear the job wouldn't be a Healer that can carry free Raging Strikes )