region 1 has 7 tiles and 1 boss tile (7)
and in those 7 tiles, we unlock the 5 T1 recipes, upgrade from 2 to 4 items, and maybe one T2 recipe
But also, we unlocked one of them from the tutorial

region 1 tile prestige vs RP cost:
60 80 100 110 120 130 140
60 80 100 110 120 130 140
we have exactly 7 points now.

region 2 tile prestige vs RP cost:
150 160 170 180 190 200 210 220
160 180 200 220 240 260 280 300

we have a shortfall of 360 even after maxing them out.

100 per region 1 hard mode tile? that would mean 3.6 hard mode tiles back there to get the 8th point.

region 3 tile prestige vs RP cost:
230+240+250+260+270+280+290+300
320+340+360+380+400+420+440+460

Now we're 1000 in the hole. Oof.

region 2 hard modes would be worth 200, region 3 hard modes would be worth 300. So we would have to do the remaining 3.4 r1 hard modes and 3.3 r2 hard modes to catch up.
What if region 2 hard mode was worth 300 instead? Then it would take 2.2 r2 hard modes to catch up.
(Hard modes are star gated, I guess?)

region 4 tile prestige vs RP cost:
310+320+330+340+350+360+370
480+500+520+540+560+580+600

We are now behind by 1400.

What does a region 3 hard mode give us? 500. So what do we need now?
We can actually get 1740 RP from the rest of region 2 hard mode. So we can catch up without even touching r3 hard mode if we don't want to.

By the way, I'm imagining that if these prestige numbers get ridiculously grindy to actually hit, we'd have some multiplier on prestige gain per service based on your progress. Like serving more flavours giving you more points, so you naturally hit bigger numbers and that feels good.

Anyway - we want to have this roughly balanced so that you have to do a little of the previous region's hard mode to catch up. So let's make the cost rise EVEN FASTER.

490+520+550+580+610+640+670
Now we're behind by 1680. Rexxy says this is OK (given that we're required to be more and more completionist by this point), so that's fine.
At this point, if you're caught up, you've completed the recipe tree and you've started on the prestige recipe tree. Hooray!

region 5 tile prestige vs RP cost:
400+420+440+460+480+500
700+750+800+850+900+1000
We're behind by 2300, which is 4-5ish r3 hard modes.
Actually, we probably don't want to worry about this too much yet, so ignore those numbers. tl;dr is
1) prestige RP will be a second 30,
2) but the costs should be WAY higher,
3) but nightmare maps will give WAY more prestige,
4) And the remainder of r5 + r3-r5 hard mode + r1-r5 nightmare mode will fill out the prestige RP tree.