If you’d like my opinion on more loop-able troops, I can’t see how they could negatively impact the status queue anymore than the current ones do. Transformers are a case of, “Once it’s done, it’s done.” Meaning the moment Alchemist, Valkyrie, and Giant Spider had been approved, any more additions wouldn’t be able to drive the point any deeper.
As it stands, it’s already theoretically possible to create an infinite loop between Alchemist / Hellcat (Throw in a Mercy for max effect) and Green Seer / Giant Spider. So any further additions wouldn’t change that fact.
If you’d like my opinion on the conceived troops:
Furfur should probably lose his ability to inflict spell damage, as Hellcat already does this randomly, and only to a singular troop. Everything else is fine, though maybe instead of Fireproof, consider Insulated. It’d offer the unique aspect of being a transformer that can’t be frozen.
Basilisk is simple and it works just fine as such. I like how it’s implied to raze the land it treks upon to lifeless dirt.
Kitsune is unique and I really like the creativity put into its spell. It’s also an interesting competitor/provider to Spirit Fox.
Mandrake looks like a fun alternative to Green Seer, it’s alternate mana spectrum likely being it’s primary reason to choose it over her. Though I’d probably say turn it’s rarity up to an Epic if only to avoid further Runic Blade abuse in Arena. Or have something done about Runic Blade, that could work too.
Myrmidon looks good. I like his synergy with Rowanne. Alastair, Templar and Royal Engineer welcome him!
Harridan I like, she’s better a Giant Spider without the crappy summon! Though she’d probably end up closer to an 11 or 12 mana cost.
TL;DR:
Overall, I like the ideas and appreciate how none of them expressly step on the toes of our present transformers. I feel the game could really benefit with more options for team comp and synergy.
Having a tough Blue legendary in your setup and immediately thinking, “Now, how can I incorporate Valkyrie into this.” I feel hasn’t provided the healthiest mentality to players. Whether more transformers would be the means to remedy this, I can not say. But it couldn’t make it worse.
P.S.
I also wouldn’t find issue with more immediate transformers like Mercy. She’s almost entirely phased out of Defend Teams as it is and is predictably counterable when she does show up.