None of my business, but the 'safety' point is a complete dead herring as baldrick would say. If you were serious about safety you wouldn't let riders risk themselves and their machines on cold tyres or road tyres in soaking wet conditions, you'd allow warmers and wets. I used to race road tyres in March in the cold and wet, but I'm older and wiser now
As for weight restrictions, please be serious
You should be thinking of reducing rules, not making more complexity, DD is a minefield already
WeeJohnyB