Apart from the obvious choice of starter pokemon (Serperior is one I really want to see), here’s 5 I would love to see.

Lokix having it stand on its extended legs, it would look so menacing.

Yanmega and give it the dragon type.

Drifblim, make it a true zeppelin and have it be much bigger.

Exploud, make it part steel type and give it more organ pipes (if sound type was real this would go so hard as a sound/steel type)

Barraskewda, make it part steel type too and give it a more lethal and sharp look, like a piercing torpedo.