No point in changing it, while tellers being accessible could be interesting i don't think it would be very balanced, Pumas would be able to force t70s into them easily and so on. Personally i'd change the upgrade to the flamer from firestorm nerfing the damage and making it come out once you tech. Would be a more diserable outcome and the unit itself would get more versatility.
Well, you're the pro. Still I would assume that forcing Sturms to close in in the mid to late game would cause heavy MP bleed since they do not vet up that great for direct combat. No sure if this is a real improvement overall.