One of the most popular Eurorack modules is the Make Noise Maths. Maths is in the venerable lineage of the Serge Dual Universal Slope Generator. I have a number of different slope generators in 5U MOTM format, as well as in CGS Serge format. It really is a universal envelope generator/LFO/slew.
I was considering two Make Noise Function modules, as an alternative to Maths. But I became convinced that the additional CV mixing ability of the Maths was need in my Portable Wave Mangling System.
I just sold Maths. Ultimately I could not like the mixer section. I found it too limited. I prefer to patch my own mixes. My replacement for Maths consists of two Mini Slews and a Befaco A*B+C. Pardon me while I duck the Maths fanatics. 🙂