Dendrite is okay for personal use (a few users), matrix-native, using the better-tested clients. IIRC some bridges work with it, but it doesn't implement the whole appservice API, which blocks you from using some of the better bridges.

I do not recommend synapse if you don't have a lot of memory. I put an extra 8 GB stick in my server for it, bringing it to 14 GB.

It routinely likes to take more than 4GB to itself, though it has become a lot leaner lately.