To answer your question... I honestly don't know but you might struggle in a few areas.
In 1st season?
This is half based on your screen shot showing £3.7M & half if you sell Benteke for a decent price.
Hmmm. Kasper Kusk is a must. Should be able to get him from AaB on a free + Agent Fee & loyalty bonus. I punted him to Monaco for £11M in the 1st January transfer window. Just checked (at 3 in the f'ing am) and after 2 seasons he's still at Monaco with a 'value' of £15M - asking price, no idea.
You should be able to get Mahamadou Diarra on a free as well who will do you for a season as rotation and is a good trainer - suppose you already have Joe Cole in the 'Old Man of Midfield' position. - That should be a new dedicated role in FM 15....
Benteke becomes a monster (think Godzilla in an Villa shirt - but with worse hair) - in my current save he moved to Wolfsburg for £16.5M after 1st season.
I kind of agree with dd though...
No idea what you would get for him 'at the moment' but if you get £10M+ you're laughing if you can replace him with someone like Michy Batshuayi (release clause from Standard Liege) or Carlos Fierro from Chivas for max £3.5M - prob less early. Don't sell him cheap though, he could make or break your season. Less risk if you sell and spread it around bargins than tempt a broken leg.
2nd must is Humam Tariq who can be picked up for (in my case) £650k. There is at least 1 'wonderkid' thread about him on here. He is just God (Allah/Budda/Jebus whatever) will walk in and turf Joe Cole to an old folks home.
Scout Jerónimo Rulli from Estudiantes de la Plata. If you can get him, spend a couple of million if it comes to it, he is becoming pretty awesome in 3rd season. No under 20 caps to his name but got work permit to come to Celtic & is now 1st choice for Argentina at the grand age of 23.
You already have Luna but have a look for Luca Antonelli (Italian international) who can be picked up for buttons as Genoa are, well basically sh*t even though they have some decent players) and he wants away before they go down. He cost me £500k to replace Emilio Izaguirre who played in the world cup (in real world) and has about 65 caps but is kinda ****.
It's 'Bargin Season Open' early on. Keep an eye on e.g. Will Hughes, Georginio Wijnaldum, Tom Ince, Jack Rodwell, John Guietti, Ravel Morrison, Nicola Leali (if you don't get Rulli), Luis Jiminez or Benoit Costil (another quality 'keeper but pretty much peaks in a couple of years).
Or, if you're not above a season long loan, scout Dorin Rotariu and/or Wilfried Zaha
You will only be able to be able to afford Batshuayi's release clause if you sell Benteke.
Kind of a very general answer to a vauge question - if you want specifics, just holler.
[And I didn't even mention the Ed.Al.Ba. word once!]