Concur. Multiple EPs > One full album.
More records = more merch to sell, which means more earning opportunities for you.
You can price them lower than a full album, but still maintain margin. Look at it this way: If you have one album at GPB15, people will buy it. If you release 3 EPs and sell 'em at a tenner each, people will buy more. As you note, some will buy only one. But others will buy all,
certainly more than would buy the full-length album. People are more willing to take a chance on a lower price. Better to get a tenner out of someone vs. nowt. Also, from the person who wants all your tracks on disc, you've just gotten 30 quid instead of 15. That's a no-brainer.
Also, as Al notes, put the songs on iTunes at 0.99 a pop. People will buy them.
Your audience will be confused anyway. You can't stop it. People, including me, are generally idiots who should be in some sort of home. The more quickly entrepreneurs realize that, the more successful they are. ;-D That said, do reduce confusion. Don't put the same song(s) on different EPs. Each EP should contain its own material.
Same goes for the eventual LP. Don't put EP stuff on the LP unless the EP stuff has been significantly reworked, like a live track or something. Each recording should contain its own material.
You have a point about it being easier to market an album in 'traditional' routes. Trouble is those routes are pretty much pointless. Nobody waits for reviews anymore. They see something trending on social media and go buy it from iTunes if they like it. If someone hears you play live and likes you, sell 'em an EP. (NB: If you're not selling merch at your live gigs, correct that oversight. Also, don't just set up a box of CDs and hope people buy 'em. Sell them from the bandstand;
ask for the sale. Forgive me if I'm lecturing you on something you already know. ;-D )
As for tracks working together as an album, I can't say many people really give a tinker's damn. I certainly don't. Not unless it's a prog-rock album which tells a story, like Rush's 2112 or something, which
can't really be released except as an album, even though certain songs are capable of standalone airplay. If your argument is that
some of the songs
can hold together into an album, that doesn't really cut it in my opinion. It's not essential they be released as an album.
If you haven't got a record deal with a major label, there's no good reason to tie yourself to their business models.
That was worth repeating. ;-)
Anyway, I hope I made at least some sense. Good luck to you!