Thank you so much for your quality input! I've recorded demos (doubles incl.) for both tracks and can certainly hear where doubles fit in stylistically in the second song, however the first song can definitely go without. As for harmonies I've already tried that and the songs can go without, at least for now. To answer your question, I do have a USB mic at home that may allow for additional tracking. It's not the greatest but may be able to fit in the background i.e. doubles in the second track.

To focus on just one song at a time is a great idea and I'll definitely do that instead. I do feel quite rehearsed with these songs but will still give myself three complete vocal takes to comp from.

For the guitar in the demos however, it seems as though the doubles get lost in the mix and aren't always on time with each other. They're both very upbeat and percussive, strum-based songs so I'm wondering if it makes sense to leave doubles for vocals only (at least in this regard)? I'd also love to hear your take on "fake" doubles. My plan for the college studio session is something like this:

Track 1
Vocals - Record x3 (comp)
Guitar (Rhythm) - Record x1
Guitar (Lead) - Record x1

Track 2
Vocals - Record x3 (comp)
Guitar (Rhythm) - Record x1

I would be extremely grateful to hear your thoughts on the above recording plan. Please let me know how I can return the favour for your advice and have a great day/night.