A Pi is though much more compact and easier to tuck away, I was thinking of still getting a model 4 with the Argon One m.2 case (https://thepihut.com/products/argon-one-m-2-raspberry-pi-4-case). However, I'm hopefully getting my Futurebit Apollo soon whose SBC should have even more power than a Raspi, and will try to install Lightning onto that. Would also be a nice compact solution and having a compact full node with LN and a hashboard would be really sick, let's see how it will work out 
I have a Argon One m.2 sitting on my desk running a node in a box (raspiblitz)
The Apollo is good, but keep in mind that it's a custom build, so unless something has changed in the last few weeks, you can't just update it, you have to wait for futurebit to release an OS / whatever update. And it's only a 512 GB drive so not a lot of room there for other stuff once you have the full node running.
What do you mean? I mean the SBC is some Orange Pi or one of those 'Raspberry clones' that have more power, but still a regular old ARM mini SBC. How would it prevent me from SSH'ing into it and installing c-lightning for example?I know, 512 is quite limited, worst case I'd in the future replace the SSD, it's a normal NVMe.
Remember that the m.2 for the argon is SATA NOT NVMe for the m.2 slot so you have a much smaller choice of what drives you can use. AND the ssd m.2 are getting harder to find.
Yup, I'm aware of that, but worst case I could take out an m.2 SATA SSD from my workstation and replace it with something better (should probably do that anyway 
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