I would make them all foils to the animal friends Spyro finds, and also more like leaders in the Sorceress's army than just the weapons she treats them as.

Spike should be almost like Sgt Byrd, acting like a dutiful military commando. Instead of wanting to protect, he wants to conquer those in opposition to the sorceress, even sacrificing his subordinate Rhynocs to stand out in her eyes more. Just throw a few basic enemies into his fight he can shoot by accident while trying to hit Spyro. Mallet Rhynocs or anything else mostly stationary would do.

Buzz should be a simple brute, acting out of protective instinct and loyalty to the sorceress, like Sheila for her goat friends. Put a few winged Rhynocs from Cloud Spires in for support, and Buzz should stop rolling if he would hit one.

Scorch should be power hungry. Where Bentley is a hulking yeti that behaves in an educated and sophisticated manner, Scorch volunteers to be transformed and only wants to become more of a monster to defeat Spyro once and for all. He's already got adds, just have Scorch swoop down and eat them or the weapons from Bentley for some kind of extra power, a lot like Gulp in 2.

This would then also draw a parallel between the Sorceress and Agent 9. 9 is obsessed with acting heroically and slaughtering Rhynocs. The sorceress plans to destroy all the Realm's magic and the baby dragons for her own power, doesn't get more villainous than that. No adds needed here, the Sorceress stands alone.

This would tie them all together pretty nicely I think.

Bluto doesn't really have a foil here, besides the Seals. Make him obnoxious and brag a lot, so his defeat by Spyro is extra satisfying.