TL;DR
Would ###_module_slot_bonus= 0.34 (or a similar value) with Epic set to level 4 and Legendary set to level 6 result in only those gaining +1 and +2 module slots respectively?

Intending to do a modded run with Mining Prod Tech disabled and infinite resources (crude oil) depletable. I'd rather have Quality levels be more distinct than adding more machine tiers, but not to the extent of !10! modules in an EM Plant.

Also, are there any inherent incompatibilities with "MoreQualityScaling" by sh4dow? I like the quality mining speed increases 😁

~Scoops

yes, you can use fractions to only provide an effect beyond threshold levels.
With a quality level of 3 you would hit the first threshold, then similarly with 6. So using 4 and 6 would do the trick.
I find that doing it this way works out best, scaling one per level is rather extreme and you end up with way too many modules.

As for compatibility, I would not know as I have not attempted to combine the two. Feel free to do so and let me know what the results are.

Excellent, thanks for the response 🙌