"That the day come"

[milo]

I hope this isn't considered bumping a post or that isn't considered bad here.

Some issues with the poem:

The number of syllables in each line vary, but usually there are seven or eight. Should I even them out, or keep it 'free'? Any bad rhythm?

If you are going to rhyme then, yes, you should try to use a consistent meter. English meter doesn't do well with "syllabics" but rather with feet. Soo . . short answer, pick a meter (most likely iambic tetrameter) and attempt to apply it throughout.