@Bobrz I didn't have to do anything to get the trackpad to work. It's an I2C trackpad, so it should work just fine, provided you're using the correct kexts (VoodooI2C and VoodooI2CHID). Make sure you have used the last Clover config zip file, not the first one, as the original one didn't have the trackpad working yet. I have noticed that it has occasional hiccups and isn't 100% supported for 3 and 4 finger gestures, but it does basic 1-3 finger gestures fine, other than occasionally needing you to lift your finger and try to move the cursor again (I think it's some kind of odd focus issue, since the cursor vanishes when you're typing). It's possible that this is because of conflicts between VoodooI2C and VoodooPS2, which I've heard of in the past, but it appears that the keyboard is PS/2, so you need VoodooPS2 unless you're using an external keyboard. I will eventually experiment and confirm that's the case, but I'd say it's about a 97% chance it is, and while it's annoying, it's not generally more than a nuisance.
As for the NVMe drive, my system drive is a high-end 500GB m.2 SATA drive and I've got a 500GB 970 EVO Plus NVMe drive that I'm currently using as a data drive. The SATA drive is fast enough that my applications all load for the frist time without any real wait (after the first load, times are cut in about half); the worst offenders being my development IDE (4 seconds, including loading last used tabs), CAD software (7 seconds including loading a file with two complicated parts), and FCP (11 seconds, including loading a simple project with some plugins used). I'm sure that I could just duplicate the system drive onto the NVMe drive, but I just don't see the need, personally (it's more effort than it's worth, IMHO). If I need a larger data drive, I can always swap it out (though that'd probably be for a huge video project, which I'd more likely just use an external thunderbolt disk array for, and use proxy clips on the fast 500GB drive for everything but final render). With 40GB of RAM (you can swap the 8GB module for a 32GB Samsung M471A4G43MB1-CTD module and then tell Clover you have 2 16GB M471A4G43MB1-CTD modules @ 2400MHz, plus the soldered-on 8GB using the info you see for the manufacturer "0" DIMM out of the factory, which isn't really a DIMM), the system drive is really just used to load programs and data that doesn't benefit from the faster drive (video goes on the faster drive), since the machine doesn't need to use swap space (which you don't really want to be used on a SSD anyway).
