So yeah,  

the good, bad, and ugly about Continuum Sculptors. Bullet points first and paragraphs on my reasoning later. For your reading convenience.

What's bad:

1. You will probably use only 1 (one) of the existing singularities ever.
2. You can only ever have three up. No more, no less.
3. The Stasis singularity is so outrageously expensive to research it might as well not exist.
4. Ever growing Dust cost force you to invest into making Dust, which sucks, because of inflation (which is something I'll avoid instead of solving)

Why is it bad?

1. You only have three slots, and have to research any singularities other than your Compression and Dilation ones. Every singularity you build increases the cost of subsequent ones, and while speeding a system can help you produce more Dust, helping you overcome the cost of the next one, that doesn't happen with any other singularity. Dilating an enemy system doesn't directly help you, you're probably not really going to need the Rip and Fold for more than some turns, and forget Stasis.

2. It's boring. Yes, that's an argument. If a faction's affinity is boring, then for what purpose does the faction exist? Far from saying singularities are boring or Riftborn shouldn't exist, I think this limitation, that starts and ends as three, should be more interactible and engaging, because it limits the cool part of Continuum Sculptors. Give us a way to increase it; give it some progression. 

3. Very little to say here. Why ever spend time researching something more expensive than a victory tech? It's called victory because you win by getting them; can't get more attractive than that. Also, now that Obliterators exist, it's faster to research, build, and fire one to forever delete a system than to research this and hold one still for 10 turns.

4. Inflation. You will have to produce Dust to afford singularities while everything else gets more expensive. Inflation is a blight in the game and we try to avoid it like the (rift) plague. No where to run in this situation.

What do I propose?

1. Limit them by type and let the cost increase work individually. Ex: instead of 3 singularities max, you can only have one of each type up, and building one doesn't increase the cost for other types.

2. Either limit them by type or allow us to increase how many slots we get. Maybe both. Ex: every tier of the Science quadrant you unlock gives you one slot for singularities; you start at one and can get up to five.

3. Change the cost to that of any other tier 5 tech, of course. You're scared of its power, but once you untie the singularities' cost and limit it to one or two of each active at once, you can just limit it to a single Stasis up and increase it's cost to not be a single Quadrinix and Orichalcix.

4. Dust sucks. If we put a fixed amount of strategic cost it will either be too expensive for early game or too cheap for late game. Increasing strategic costs are an idea, but I like another even more: make them cost strategic resource upkeep, and maybe make it increase over time. Building a singularity is free (besides spending one turn in a system's queue) but it will drain one Titanium per turn. Then 2. Then 3. As long as you have Titanium you can keep it going (or end it early of course), but if you run out, the singularity stops, and when a singularity stops (either on purpose or because you ran out of "fuel"), it gets put on a cooldown and you can't activate it again. Good for early game, because you can activate it on a short window at a time from turn 3, good on the late game, because it will come a time you'll run out of a strategic resource unless you can grow your production of it faster than the singularity's consumption. Now you can keep the Rip and Fold up for only as long as you need them, and Stasis only as long as you can put up with the very expensive upkeep.

Hope you like it.

I actually have nothing to add to this currently other than: +1

I like all of these suggestions. Particularly I quite like tying them down only to Strategics, and providing a growing upkeep over time. It feels like it follows the same design path as Kapaku, but in a more complex form and from an angle of Upkeep for buffs instead of permanent changes to the environment.

Since the game has had more percentage changes to resources lately, I think it would not be unreasonable for the Upkeep to increase by fractions of Strategics each turn instead of a rapidly increasing 1-2-3-4-5-6-etc.