The ’preamp’ is essentially a cash grabbing strategy by certain manufacturers who went to the umpteenth level to do a ground-up design/fine tune a preamp to a specific power amp. For example, Luxman... they designed a wallet abusing preamp (c900u) for their m900u power amp and the latter sounds the best only with that specific preamp (A few other manufacturers fall in that same category locking you into a stack).
If you didn’t get stuck with such a cash grab manufacturer strategy, feel free to mix/match whatever, find a integrated amp or a dac with a decent sounding preamp mode, i.e., don’t overthink the preamp. It isn’t the greatest thing that happened to hifi since sliced bread.