I would say that the EotGs has a pretty clearly defined purpose of being a flexible support behemoth.
It's a support behemoth, but how it supports is rather badly defined. It's supportive effects are all over the place and (especially without slann) rather unreliable. It's powers need to be more focused. And preferably it should get something that isn't random in there.
Also, it suffers a fair amount from powercreep statwise. But that's a seperate issue
I get that you don't like the Slann's current summoning mechanic, but I fundamentally disagree with your assessment of its engagement. I think you have an overly narrow concept of how BwV and Cogs are "suppose" to be used. Like the EotGs they add flexibility. The flexibility is amplified by the Slann's ability to generate CCP. If you are casting cogs, setting it to slow and forgetting about it then you are likely misplaying the army. Same goes for BwV if you forget about it's range increases. In every game at a tournament that I have had go to full rounds I have had to both slow down & speed up time at various points in the match. I have also had to make use of the extra spell range and the Slann's ability to change his spell lore at the end of each of our hero phases. Not to mention the added benefit of getting +1 save and rerolling saves from bwv and cogs. I can't think of any wizard who makes better use of Cogs and BwV to the fullest potential than a Slann does.
With respect to the cogs & BwV my gripe is mostly that they're always going to be sacrificed to the slann. Though the point-cost of endless spells & rule of one are mostly what ruins it here for me. The slann makes the best use of the BwV so your skinks (or the occasionally allied wizard )will never get to use it. Which I find dissapointing, especially as it gets sacrificed for a mechanic I already don't find super interesting to begin with.
Ignoring for the moment that I don't like the CCP-generating mechanic the use of Cogs & BwV itself would be fine-ish.
It seems to me that if you aren't finding rewarding play decisions with the current summoning build then you are either playing against none challenging opponents or you are failing to provide your opponent with a challenge.
There's rewarding decisions, but none of them are related to the summoning mechanic itself. The question "should I burn this spell for CCP or hit that target with some mortal wounds" is nearly always rather obvious, and depressingly often is "go for the CCP". Decisions like "should I summon A to kill X, or summon B to grab an objective, or C to stall Y" are all interesting enough.
Let me put it this way, the playstyle as a whole, of a master summoner who adjust his army on the spot and calls down whatever reinforcements he needs, where he needs them. Is interesting. The mechanic of actually generating the CCP, the fact that it completly hinges on the slann & that the only real reason the slann even needs to be on the board is as a range indicator for summoning (the handfull of spells it actually does cast could just as well be done by a skink replacement, especially seeing as all the good spells the skinks knows anyway...) is what I find boring/bad.
why do you play seraphon? you seem to dislike every unit and ability we have.
I like the fluff. I like dinosaurs riding dinosaurs.
As for actual units, I like most of em, though a lot are massivly undertuned by now.
As for units/mechanics that I actually dislike (and aren't just undertuned):
- CCP generation
- Slann not doing much besides looking pretty and generating CCP
- Skink heroes not doing much besides looking pretty and doing the 1 spell/ritual per turn
- Skinks cohorts being utterly useless besides being cannonfodder. Admittadly they're great cannonfodder, but it'd be nice if they'd be more than bodies to be chopped up.
- EoTG effects being a mess without clear focus
And that's all really. The rest is mostly a matter of things being undertuned, but the basic concepts behind them are fine.