Mark for installation
I propose a "mark for installation" - feature as seen in synaptic-type package managers. Since I am living off-grid, I do much of my work offline, i.e. answering mails in a client. F-Droid keeps the repo lists so that I can study them offline, if I could mark packages for install, actually downloading them could happen fast and effectivly at the press of a button as soon as I'm on a connected WLAN.