Field-expedient FA knowledge is the first thing I'd say - improvising is fine for FA purposes ... if it's worse than that, it's all just reassuring hand-holding until the helicopter arrives isn't it?
Water, which you'll have, although I assume a 'sports-drink' will flush grit out of a wound just as well ? A small folding pocket knife (non-locking, and with a cutting edge not exceeding 3" of course
), tick-hooks, and some decent tweezers (like Old Bills Silver Grippers), gaffa-tape and something to pack the hole with if the edges are too far apart / ragged out for you to tape up reliably (another reason to wear a bandana under your helmet). A couple of zip ties might come in useful, or a pedal strap ... that way you can fix the bike too / instead.
Gaffa-tape butterfly sutures have got me out of err, a number of scrapes in my time.