I have a stripboard layout for the LM13700 based VCA on MIAW ( search youtube for modular in a week if you haven’t seen it already) they aren’t great - but they’re an easy build and work. (they sometimes leak a bit and the bias is touchy which is why I say they aren’t great.)
Details in my build thread along with the stripboard layout: My first DIY modules - starting a Kosmo format build
A simple LFO is also nice to have when you’re first putting things together. There’s one in my thread but I’m really not happy with it. In fact a better LFO is high on my list of things to build next. I have the LMNC 1145 and it’s amazing…but…it’s kind of too much for a lot of things. Though as others have mentioned a sequencer, MIDI to CV converter or some other controller with CV outputs is also really helpful to have and something you’ll pretty much need at some point.