I’m using a streamer/dac into a Amp designed just for the streamer. Perhaps I drank the Koolaid but it sounds better this way. A buddy uses his steamer the same way too.
The rule of thumb that separates are the best way to go in 97.87% (made up number) of systems is so but if you only stream maybe if equipment has synergy ($pelled with dollars signs) a pre maybe not critical.
Another vote for Qibuz.