If you think you will need more storage space, with a NUC, you will probably need either an external drive or a NAS. If you get a tower, you can add the drives internally. That is my one regret with a mini-pc, I can’t add more hard drives.
In fact I already have a Synology NAS, that I have my backups on. I guess as long as the data connection doesn’t need to be high speed, I can use some space on that (or even upgrade the 2TB space in my NAS in the longrun). So I probably don’t need a full tower. My main concern was, if a NUC would be overpriced in relation to other similar products.
I have a NUC as a family computer and it works well. For my server, I bought a Minisforum mini-pc that works well. My brother got a Beelink mini-pc that he likes. Those are other options you can check.
Ok, I will check them tomorrow (I really need to sleep soon, as its already 2am). I mainly want to experiment with different technologies, that I already know from work. Openshift, Docker, Puppet and Ansible for example.
My homelab started with a Synology NAS as well. At first I put a few VMs on the NAS, and then I expanded the homelab to include a single PC. I almost bought a NUC instead. I’m glad I didn’t, because the NUC only offered one advantage: it was small. Beyond that, the PC was better in every respect. More expandable, more configurable, etc. I decided to get a really small PC case intended for home theater PCs to get some of the smallness offered by the NUC and called it good.