I am not sure if you have any external equipment? I guess the effects you will do with your guitar pedals?
Your original plan to use the Plaits & STO is I think a better idea than Plaits & Kinks. If I were you I would look into at least one more filter, I am missing LFOs I think, a Eurorack mixer before putting the signal to the outside world and do you have an external sequencer? If not you might want to consider that too.
The Maths is of course a good module but for small racks it's rather large, so you might want to replace it by a smaller more efficient module.
Even if you want to keep this as a small rack, go for at least 3 rows instead of just one here, keep at least one row empty for future use.
Good luck and kind regards, Garfield Modular.