Positive version of the word crowd
Solution 1:
I personally find nothing negative (or positive) about the noun crowd. (Although the verb crowd could be different.) I suspect you are putting too much emphasis on its synonyms. Most (if not actually all) synonyms are related to a word, but they aren't actually identical.
However, an alternative which I can't force (so to speak) into a negative connotation in the same way is group:
[Merriam-Webster]
2 a: a number of individuals assembled together or having some unifying relationship
// a study group
So:
A group gathered to enjoy the sunshine and company.
If you need to be explicit about the size of the group (as crowd normally implies), you need to also use an adjective:
A large group gathered to enjoy the sunshine and company.