I've built, and will continue to build my own "workstation" any time a refresh is needed ... it's effort, but I've always believed that what I save in the cost just to have a name on a box, means I get to put more into the components. Instead of a $500 dell, of which $250 is components, and $250 is the name, I have all $500 in components.
Don't need their support, don't need their bloat ... just the best matched components I can string together, as others have pointed out.
It *is* some effort, and if the magic is gone in that effort for the OP, then the NUC and its equivalents is probably the answer. For the rest of the family, I just buy "bare-bones" nuc's, slap in ssd's & ram, load an OS, and they are good to go. Or, they get a laptop for traveling requirements. Don't know if any of the NUC series will work for OP, but why buy a "quiet pc" from someone, when these days it's most likely just a nuc or a variant of a nuc?
Buy it yourself, spec'd to meet your requirements, and/or slap in even larger ssd/ram than what you can find out there for the casual end-user market.