As a brief aside, the Delver boat has sort of sailed with the rotation of Ponder - the one delver based deck I've seen at an FNM since the release of RTR has been underwhelming at best.
That being said, here are some thoughts:
1) So realistically the way you intend to win is via the flipped Delvers or Talrand's drakes, right? In what way are you not totally ruined by Detention Sphere or board wipes like Supreme Verdict or Mutilate? I know this is an obvious flaw with most decks, but here you look particularly vulnerable as nothing is bigger than a 3/2 and all of them need some time or special trick to be dangerous (2x Electrickery becomes a game ender for you here).
2) How do you handle the mid-range stompers/beaters? I'm thinking of Thragtusk and even, to a lesser degree, Loxodon Smiter here. Pretty much anything with a toughness higher than 3 has you hosed. Sure Runechanter's Pike could prove useful, but with Tormod's Crypt, Deathrite Shaman, Cremate, and most notably Rest in Peace in standard, having those spells in your graveyard isn't something you should completely rely on (I say this as I'm running a graveyard based Golgari build...).
3) Augur of Bolas is solid but what are you reaching for here? None of your instants or sorceries are really game changers that I can see. So what're you reaching to grab?
4) Think Twice is likely a better alternative to Thought Scour for you here, as it will let you draw more than once (while still at instant speed).
So to run down your questions...
Are there any cards that should be exchanged? See #4 above. Also, you should think about either adding some larger creatures or at least something else that gives you an offensive weapon.
What should be in my sideboard? You're going to want a fair bit of enchantment/artifact hate as most people run things in their boards that are designed to stop Snapcaster Mage (lest we forget that Delver was the dominant build pre-rotation). To that end, Smelt for artifacts and perhaps things like Negate to counter enchantments before they even hit the field - but keep in mind, if one Rest in Peace makes it onto the board, you might as well scoop. I'd also suggest Annihilating Fire as a 4x of in the board - to deal with those pesky Gravecrawlers and Geralf's Messengers.
How should I use my burn spells most efficiently? Obviously this will vary from game to game. If someone's deck is built to ramp into a huge creature, you want to torch the ramp creatures. If they're running a Blood Artist centric zombie deck, you want to blow up the artists. G/W aggro, pretty much whatever you can actually kill is good. But keep in mind the extra cost for Annihilating Fire is totally worth it when you never have to see that zombie again.
What to look out for in the format? At least at my LGS things are VERY zombie and aggro heavy at the moment. Desecration Demon is a common item to run into that could be a major problem for you. There are still the Azorius folks who are running 4x Restoration Angel that will pretty much ruin what you have here as well. It really depends on your local meta; however, you should definitely be ready to see some really fast play with creatures bigger than your flipped Delvers hitting the field on turn three or four.
General tips...? This is a personal opinion, but R/U wasn't the stronger of the Delver builds when Ponder was still available and I think the strategy has lost a LOT of steam - perhaps to the point that you try to be more creative with what you have and make an Izzet build that's more outside of the box. Pairing Blistercoil Weird with Dual Casting for instance to give you +2 copies for every spell you cast (if not more). That combo makes all sorts of otherwise mundane moves really nasty (I'd happily make two copies of Talrand's Invocation or even Thatcher Revolt with a three Trumpet Blasts). Then again, I never liked Delver to begin with, so maybe that's my prejudice against it coming out.
Will this deck be good enough for standard at all? Perhaps this is where I was headed in the previous answer, but I'm inclined to say no, it won't make the cut. With the amount of things that were integral to Delver working that rotated, paired with the amount of obvious Delver hate that came in RTR, I just don't think it's a viable strategy anymore. It's worth a go and might do damage at your LGS, but my money is that you likely won't flip them as often as you like and will, more often than not, end up getting smashed by a horde of creatures that are bigger than you can manage.
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