Basing this simply on SPS is not a very good idea in my opinion. Adding it as a way for new players to achieve Mav status would be a good idea, but telling me I can no longer access Mav chat even though I have purchased 5000 packs and thousands of cards simply because I don't have 100k SPS is ludicrous. You will be ostracizing as many voices as you hope to gain in the future, if not more.

Enforce the rules. That's what they're there for.