I think VIP's should get a boost when they grow cacti or drugs not to make pay to win but make it more fair for the person who spent 10.00$ on the server. Just as a extra perk for the donor. I think it can help you as well cause it makes more players want to donate.

No,
Drugs faster grow rate with more people

This is both a good and a bad idea, good because more people would support for the server by donating.
Bad because they would get a big advantage.

Would you want VIPs overpowered and ruling the server though?

No.

Sorry, but that is just too overpowered. Besides, pay2win is subscriber, not donor/VIP.