B737,
No partner
needed as such, but in my opinion if you're going to be flying cross-countries on your own (QXC's excepted) you may as well offer the seat to a like-minded person who will offer you the same in return so that you both benefit from the experience.
In that way, you may only be logging the hours you pay for, but you're both building your experience and you're also working together as a crew - those all-important CRM skills!
cm