It's really interesting how many people ask the same question with the same implications. First of all, Egypt's military needed a major modernization, mostly in the air force as well as the navy. Those two are the main branches that really needed a lot of help.
Then there is the issue of the US through the peace treaty military financial aid and the VERY WELL KNOWN story about the US not supplying Egypt's 4th largest fleet of F-16s in the world the AIM-120 missile and only an upgrade of the entire fleet of under block 40 Falcons to be brought up to blck 40 standards but still, no approval for the AIM-120 despite having the AIM-7M which has a 70 km range instead of the AIM-120's 100+. So the high-end BVR missiles being denied to Egypt (and much of it is also Egypt's fault as we've discussed that on this thread to be fair, they could've done a lot to get the approval of the missiles and one of the main things was signing the CISMOA act which Egypt refused to do so for the longest time until a few years ago. That would've eased the US' mind about approving the missiles because the CISMOA is essentially what guarantees and protects and regulates the use of sensitive American avionics and communications systems. Refusing to sign that treaty was very strange to many of us. We couldn't understand why since it would only help and not hurt in any way since they eventually did sign it!?) so that aspect was high on the list to go get along with the modernization.
The other reason was a new policy to not depend on only one or two sources of weapons (and their weaponry) and to expand that. So the first thing was a whammy when the 2 Mistrals became available and Egypt had been looking at Rafales since 2009 and suddenly, that mega deal comes to fruition including the FREMM frigate and the 4 Gowinds. Then the 4 Romeo submarines needed a major upgrade and who else to go to but the Germans for 4 Type 209s. Then the Rafale was so liked by the EAF (we can also see how much it's been liked by India as well) that we had an option for 12 more over the 24 we bought and went to execute that option and ran into snags with the French on financing. So that came to an end. In the meantime, we had already agreed with the Russians that all our MiG-21s and F-7 Airguards needed to be replaced and so we went to buy 50 MiG-35s. So that's where those came from and of course, the whole time we had in mind for some air superiority aircraft and so the Su-35 deal was signed. With those 2 aircraft gave the EAF some serious BVR capabilities to add to the MICA IR & ER in the R-77 & R-73. This was also something that was discussed back in 2011, so it's not a surprise.
With the snag on the Rafale came a snag with the additional navy equipment namely the additional FREMM frigate we wanted as well as another 4 Gowind corvettes on top of the original 4 we received. As a result, we talked to Italy for their FREMMs which are essentially a close variant of the French FREMM to keep things close as well as expanding the naval element by buying 6 Meko frigates from Germany and with the pair of Italian Bergamini Class FREMMs, a deal for 24 Typhoons came up and I personally think that because of their compatibility with the Rafales that they were agreed on to augment that variant of fighters in the EAF as well as add to the MICA BVR missiles and the order of Meteor missile to get even more meteors.
As far as maintenance, the EAF hasn't had any difficulty maintaining US, French, Russian and Chinese aircraft in the past and so it shouldn't be an issue at all now with even newer aircraft that have easier maintenance routines to them. And the Rafale were easily and quickly absorbed by the EAF and their manitenance crews and with our previous Russian experience, the MiG-35s have also been easily absorbed and so will the Su-35s when they come InshaAllah. The Typhoon should also be a relatively seamless transition into the EAF (if that deal goes through) considering the similarity to the Rafale and my guess is those two will function as a single unit in missions and in technical aspects. So that's the jist of the whole different arms purchases.
EDIT: The 46 new helicopters (the Ka-52 Nile Crocodiles) was brought out of the need to expand the 46 Apache attack helos that the Armed Forces had but also because the Long Bow radar was denied to Egypt (also most likely because of the CISMOA treaty not being signed) and the Ka-52s also were a lead into the eventual Ka-52K Katrans which would be the naval helo to equip the Mistrals. That was born out of that entire deal since that was what the Russians were going to do with those 2 Mistrals and Egypt is just following that line of thinking because it works well to have that attack capability off the LHDs. But that could also change as things develop.
New photos of transit maritime training between the Egyptian frigate El Suez and the Spanish frigate Santa Maria in the Egyptian Southern Fleet in the Red Sea a few days ago.