Um..
I don't see how this is very nessasary and practical. For instance, higher spawning rates for elites would just lag everything, and it'll be very unfair.
Not to mention that most of the ideas are very far-fetched.
Let's see let me weigh some pros and cons to this idea.
Pros: None
Cons: Encouragement of further elitism amongst the donors vs the cits, the amount of lag that would be generated, the further enforcement of the pay to win notion and many more downsides.
Higher spawn generation rate will make Towny have lag chunks every minute by this.
Supreme makes no sense to me at all. What you said there is that different types of spawners are generated. What do you mean by that?
Ultimate has no use here. Players can be in two towns at once because there's Alpha and Beta.
If you added specific worlds for certain ranks, that will basically make all ranks unfair towards citizens. And the perks you suggested will cause amounts of lag.