One thing you need to understand about social marketing is that it's not a passive, set-it-and-forget-it thing. Okay, you've set up a Facebook/G+ thingy and put like buttons on your web site. Cool. That gives you a number you can show to people (investors, advertisers) -- but by now anyone with an iota of savvy has figured out that the number of likes means nothing. Whether you want to get investment, advertisers or just drive people to your web site for your own nefarious world-conquering purposes, you need engagement. That means posting things that are clickworthy to your social media pages and/or tweeting all of the time. Let it go more than a few days, and people forget who you are. Pummel them with spam, and they'll remember, but not in a good way. They'll not only unlike/unfollow/-1 you, but you've just created a viral word-of-mouth campaign that's just about the opposite of what you want.
"Tricky" SEO is no longer a real thing. If you find a new trick, you can bet that that hole will be plugged with a vengeance in short order. Google, Facebook, Twitter and all of the rest of them have their own bottoms and bottom lines to look after now, and they don't need anything showing up that's going to hurt their utility or perceived value. If you want to do "SEO" (which is really just another name for effective marketing), you first have to offer real value. If you've got nothing to sell that anyone wants to buy, it really doesn't matter what else you do. If you've got something that people want (or that you can convince them they want) then you don't need tricks -- just hard work.