From everything I've read about this aircraft, it does seem a bit crap. Lockheed Martin is trying to do too many things without first establishing what the package is good at.
The F-15 Eagle is a superb aircraft, it's fast, it turns very well, it's very good for gaining air superiority and holding air superiority (isn't that the point of a fighter?), it can be flown high or low depending on the mission and it can even be a good close, fast air support weapon for troops on the ground. Most importantly it has been tried and tested in front line combat both air-to-air and for ground strike roles and it has dominated, I don't believe a single aircraft has been lost in air-to-air engagements. In my opinion it's the perfect fast jet, although I am slightly biased as it is my favourite.
The F-15SE is an upgraded version, plus it has stealth capabilities. It's also a lot cheaper. So why did the MOD decide to go with the F-35's as one of our main air assets when there are other, cheaper, and proven more effective options? The F-35's will be great for defending the fleet, I have no doubt. Although I can't understand why the MOD have ordered these aircraft to work alongside the Typhoon in both conventional roles and carrier-based roles. There is no logic there for me.
If you're going to hybridise a bomber/close support aircraft with a fighter, then in my view it would be good logic to go with something that already works and is known to work. In the process you'd save a lot of money.