Present tense is fine for expressing a thing that is always true, even when the frame-of-reference is the future.
I'm visiting Jan next week. It is always good to see her.
But "it will always be wonderful to be with Jan" is not idiomatic, at least not in the typical context where you're wanting to say that it is always good to be with Jan. You would use the future in that way only if you're heavily stressing the fact that you never expect that to change.
The rich get richer and the poor get poorer, and it will always be
I've known Jan since childhood. It is always good to see her (or him), and I cannot imagine us ever falling out, since we are such good friends. It will always be wonderful to see Jan.