Same here. I really tried to get used to them, for many many hours, hoping that it would "click" with me eventually ... but they've been useless at best and extremely annyoing at worst, so I keep them turned off permanently. The only situation where I would consider using them, would be when Nintendo gave us the option to turn the sage avatars off but keep the ability accessible. Until that happens, they all stay in limbo.
And TBH I don't see the point. They could have added the sage abilities to the "rune wheel" or gave them a separate selection with the same setup altogether. An easy-to-access quick menu, no NPC's standing in the way, no need to toggle the entire ability on/off every time.
Add Rijus Ability to the "arrow fuse" section, so you can just pause after drawing your bow and decide whether or not you want a lightning bolt to zap whatever is hit with the arrow, or rather use a different "material" to fuse to the arrowhead.
Sidon's ability could auto-activate if Link holds up the shield, just like Daruk's Protection. No extra button input needed. Of course with a recharge timer so the player doesn't become outright invincible. Alternatively, it could be added AS an extra "shield" in the shield quick selection, so you can manually pick when and if you want to summon th water bubble.
Tulin can stay as it is. One button while gliding for an extra boost. The ability is useless while you're not gliding so just scrap that entirely.
Yunobo ... how about charged attachs like with Urbosa's Fury in BotW? You aim while you charge, release to shoot him, then a small cooldown. No extra buttons needed. Alternatively, it could be added AS a "weapon" in the melee weapons quick access menu, so you can manually pick when to 'summon' him and blast stuff to bits.
100% agreed for Mineru tho. It's just too powerful, shields Link from damage, nullifies fall damage entirely, makes you able to just waltz over Gloom ... the downside has to be bigger to make the entire setup balanced, and cranking up the battery usage would be a nice way to solve this.