It's an interesting idea, but after some mulling I don't think it's too likely. The thing about these RMC-makeovers is that they make sense because they are recycling these huge expensive mega-woodie structures that fell out of use only because of a poorly adapted track system that was impossible to maintain. Mine train coasters are much smaller and already use steel rails, so they make less economic sense to recycle and they don't have as many maintenance issues in the first place.
Then again, maybe a park like SDC wants to keep the legacy of a particular ride alive with a new system. However, if they do, they have a lot more options than RMC. I believe at one point the park actually looked at replacing TNT with a newer, larger Vekoma version? There's also Mack and Gerstauler systems which could be really good.
After they took out the backwards facing seats I started thinking that replacing TNT with a new Gerstauler version of the same basic thing would probably be a big improvement. Keep the helix in place, and innovate from there. The helix beginning of the ride is the only really special part of TNT that's left right now.
I think the park feels like it needs to work really hard to keep pushing "new" rides though, so the idea of replacing/upgrading an old attraction may be a wash with them. Better to take it out completely and throw something gimmicky in like the world's tallest suspended wild mouse.