I'm against a lower exp rate being added if it's just going to be the same as the other modes.
Something I suggested before the server released was that further down the line there could be a 'realism' mode added. Realism mode would have an exp rate of 1.5x (or 1x/2x) & players would be restricted to only OSRS features. So there'd be no voting (or at least you'd get no coins), you wouldn't be able to use the portal at home, you'd start with an OSRS starter pack, BXP wouldn't apply to your account etc etc.
I doubt it would get much support, but if we were to add a lower exp rate that's how I'd like it to be implemented anyway!