Thanks! I just tried testing the @-ing a Lemmy community, Pixelfed treated it as if I tried to find an user and said "no match found". I tried pasting a link to a pixelfed post in the "link" field in Lemmy post creation. It recognised the post/user but the shared media on Lemmy is ant-sized and requires more clicks (or a click on the link to get to pixelfed website).
I have chosen a mainstream instance as I believe it's less likely to be shut down due to e.g. its admin not being able or willing to pay for the server - so for stability. Do you think it's a wrong way of thinking? I'm new in Fediverse, and I'm aware that more small instances is better than a few big ones. But when I want to share something widely having an account on a big one seems reasonable?