Hi LilP,
You are welcome. Okay good to know that you don't have a (HP) space issue, then of course you can ignore all my comments regarding HP-space :-)
I am quite happy with my Doepfer mixer modules A-138p and A-138o. The A-138o is for the output and the A-138p provides you a four-channel mixer that's chain-able, and that's the part of it that I like most that you can just add another A-138p module if you need after a while more than 4 channels, you can add just another A-138p (no extra A-138o needed by the way) and you got 8 channels instead of 4 channels, etcetera. If I could effort it, I would have gone directly for the A-135-4A/B/C but it's possible to mix-up the A-135-4A/B/C with the A-138p, so you could start with the A-138p and in the future add an A-135-4A/B/C set to it.
Another mixer that might be interesting is the WMD - Performance Mixer, then you get straight away 8 channels and another 2 stereo channels can be added with the Channels Expand module.
Filters is really difficult and might be very personal as well depending on your personal taste. The filter I am most happy with is the Doepfer A-124 VCF-5 WASP filter and recently I rediscovered my Waldorf - VCF1 filter, if you get to know it, that one is pretty nice too, it's on offer at some dealers in Europe. Also the Doepfer A-106-5 SEM filter has its charms. I got an Erica Synths - Black Polivoks VCF as well but it somehow disappoints me, I usually like Erica Synths products but their filters can't convince me so far. And, bit of a cliché but last and not least... I have to admit that my current setup is a bit weak on filters (other than the above mentioned ones), I just can't find more/nice filters that make me totally happy. I have a bit the same with VCAs, can't find the perfect one, other than the Waldorf - DVCA1, that's by the way a fantastic dual VCA. I just ordered a second one because, though it's big in HP-space, it's seriously nice and good to use. No other VCA really had convinced me so far. The Erica Synths - Black VCA is quite okay as well but not as good as the DVCA1.
I am quite happy with my Intellijel - Audio I/O module, it's my main audio input/output interface module, the Befaco - Out v3 is not too bad either and has as a pro a headphones output. If you like XLR ins and outs then you should consider the ACL - Audio Interface that's a pretty good one too I think.
As some members mention here in this Forum: There is no real bad or real good, it's at the end totally up to you what you like and what you prefer to use. If you have an opportunity to test modules at a local dealer then you should use that opportunity, like that I could rule out some modules of which I really thought I would love them but at the end they were pretty disappointing.
I strongly would recommend to start slowly with a few modules only, build up experience with those. You not only gain experience with those modules but you already get a clearer focus for yourself where you like to look at more closely and from there you decide then to take a few more modules, again build up more experience, etcetera.
Have fun with it and enjoy modular, it's great! :-) Kind regards, Garfield.
Edit: Removed typos.
For review reports of Eurorack modules, please refer to https://garfieldmodular.net/ for PDF formatted downloads