I've been playing Balance for a while, and although I'm not a great player, I do like to think of myself as above average. Age has caught up to me and with time, my response time has gone down, but I'll make an attempt at many of the concerns that Balance Druids have had - and will continue to face if changes are not brought into place.
This is not a complaint thread to buff Balance druids, it is not even a complaint about where our numbers are right now - those are easy to tweak. This is a list of issues of the Boomkin playstyle itself that makes the spec frustrating to play. I've included basic suggestions, but in all honesty, between the 100+ suggestion threads on boomkins since Beta, I don't think that devs are short of ideas. At this stage, I humbly request devs to please communicate on the state of QOL issues of Boomkins.
Issue: Too much of a up-down cycle in DPS
Cause: Eclipse and out of Eclipse durations / Nature's Grace (NG)
It is incredibly frustrating to have to STOP dps entirely to prevent going into eclipse at the wrong time. When NG procs at the start of every eclipse, the damage goes up a lot and then dwindles down a lot. The other problem it creates is that our Mastery - Total Eclipse - is valued at zero (even if someone had 25% mastery) for the 50% of the time spent outside of Eclipse. It is due to this very fact that mastery - the supposedly knob to fine tune DPS will never be a desired stat for Moonkins over Crit or Haste. Right now, if it has mastery - reforge out of it.
On top of that, we already are the unique spec that needs to "hold" a particular eclipse depending on the time of the fight (AE vs. Single) - which is counter-productive to what we are always told - wanting to cycle through your eclipses.
The solution would be relatively simple - Drop the Eclipse "dead zone" entirely, and reduce Eclipse bonus dmg to bring overall DPS in line. What it allows us to do is then just worry about being in the "right" eclipse and not have to worry about ever being out of Eclipse.
Issue: AE is very Clunky + Spikey
Cause: Wild Mushrooms, Hurricane/A.Storm, DoTs, Nature's Grace
Balance is now the only spec (to my knowledge) that has almost no secondary interaction with our AE spells. No DoT spread, no "moving" AE, no "fire and forget" AE. On top of this, Nature's Grace is too large a contributor to AE DPS. During NG, casting Hurricane does about 100-150k dmg for a raid-geared boomkin. Out of NG, this number drops by ~ 30-35%. In my relatively bad gear, I did ~ 180k DPS with NG, during Solar and trinket procs. A minute later, it was down to ~ 50k DPS AE just because I was not in Solar and no NG, and no trinkets. This spike is too much to deal with.
We need better interaction with wild mushrooms - even a glyph of Spectral Mushrooms (yea, it's a corny name!) - that would change WM damage to Spellstorm would help during Lunar. DoT spread at a reduced damage level, hurricane fire and forget, and many other ways to make AE less clunky. Challenge modes exasberate this problem further.
Issue: Starfall hits unwanted targets
Cause: Starfall hits unwanted targets!
Please devs, this is already a huge issue in many fights. Starfall makes up for ~ 15-20% of a raid geared moonkin's total DPS. With 2-PC, that number is even higher. Not being able to use it on fights like Garajal (kills spirit totems), or Wind Lord - this isn't even counting heroic - is a major issue. The glyph of Focus is a step in the right direction, but it still doesn't solve the problem entirely. Making it a smaller radius from your selected target makes it much more manageable.
Issue: Cooldowns are too powerful
Cause: Inc/NV/CA all synergize a bit too well
This is more of an opinion; I'm sure I'll see be flamed for it. Not being great geared, most tanks cannot hold aggro off a moonkin at the start of a fight. With Pre-Pot, trinkets, and all CDs, boomies are doing upwards of 150-200k (not including Lust/Hero). This is plain stupid. All 3 CDs share a common 3-min CD, and due to their duration, a 15-second portion is always chained together with on-use trinkets etc as well. During this portion, the DPS is way too high.
The problem is when a fight calls for short intermittent bursts on a 60-150 second intervals, moonkins start coming up short. This also contributes to the spike in DPS. Normalizing this would be a lot better to make boomkins' CD management smarter instead of just "Fire when they're up. Mostly"