I love the Gripen, I think it's a wonderful fighter, as I have stated in one of my posts - a beautiful and graceful get powerful airplane. I like the F-18 Hornet, but I think it could have been built better. It's still fairly a new plane, considering nowadays.
The problem with both these fighters, the Hornet and the Gripen, I believe, are the engines, the General Electric F404. I don't know the Swedish company that was subsidized by GE to build the engine for the Gripen. First of all, I think the F404's thrust factor stinks. Yes, it is a very reliable engine as I've watched and read from crew chiefs, and yes, the F404 will push the Gripen to Mach 2, but why not the Hornet, and it has 2 of them?
I think this a good reason why the Hornet is not a GREAT dogfighter, just a good one - it has mediocre thrust-to-weight ratio. Look at the current F-16s - they're pushing 29,000 lbs of thrust from GE's F110 engines. Every F-16 pilot will tell how powerful that engine is. You don't hear that from Hornet pilots.
I think the F-18C & D model would greatly benefit from engines that get at least 20,000 lbs of thrust. It would make the fighter faster and more maneuverable especially in dogfights. The jet already has exceptional low-speed agility; it needs an exceptional high-speed punch. There's no need to retire these aircrafts so soon - look at the Eagle, it's still serving as a front line fighter for over 30 years. The Hornet is only around 20 years old but has newer technology than the Eagle.
As for the Gripen, I think implementing the F-16's GE F-110 engine would make the Gripen a phenomenal fighter, giving the fighter over 10, 000 lbs more thrust. Of course we all know this is with the afterburners on. Supercruise would be a great addition. Additionally, the Gripen's fuselage would have to be enlarged to accomodate the new engine. Possibly one of the Eurofighter's engines would fit nicely? And one more thing - it would be a shame if England, Germany and Italy retire the absolutely marvelous Tornado, both ground attack and interceptor. That would truly be a waste.