Your points are valid, but still it's more an entertainment to use him, than requirement.
On the servers with runes you have a simple choice of 5 attacking combos: Wee / Void / Genie / Cyclops+Hydra / Archer+Rev (or even without Rev). Add 2 or 3 control heroes: medusa, wolf, dust. Add any meat shield upfront for crabs/cauldrons, it can be your level 50 dragon lady, doesn't matter a single bit. You're done. Add any support/damage heroes if you're unsure, but generally 3 attackers are enough for any def tower, 4 max.
And for exp, I just run with moon-wee-medusa-witch-horse. Wee autoshots everything.
Of nearly 70 heroes, the real meta is tiny, ~15 heroes are mandatory, 5-10 are pretty helpful depending on your choice, 15-20 are helpful, but are way worse than meta and not recommended to use, others are plain bad.
Mandatory heroes are:
- Void, Wee, Archer, Cyclops, Wolf, Moon, Spider, Horse, Spectral, Bone, Bard, Medusa, Dungeon Man, Witch, Kraken
Pretty helpful, depending on your choice:
- Ninja, Corgi, Rev, Hydra, Kaiju, Water Wyrm, Plant, Bro, Dust Devil (great for 500+ temples and war offense), Ancient Idol (great for 500+ temples)
Helpful, but don't fit in the current meta:
- Cosmic Elf, Druid (you could use these two shield breakers, but they aren't needed outside war, and war's too easy anyway, so it's a waste of resources to evolve them), Dracul, Plague Mogul, Mega, Cutie, Genie, Silent Spirit, Roller, Spikey, Frosty, Understudy, Yeti, etc.
- Snap, Monk, Skeleton King, Centaur, Dragon Lady, Faith Healer, Assassin, Vulture, etc.