Obviously it'll be down to the OP what he thinks are good enough to succeed his, and likewise what you think will are good enough to succeed yours, but from a personal point of view, I was never that keen on the 752's. Nowadays, there's not many decent £600 floorstanders around. I'd say you have to start with the Monitor Audio RX6's, Rega RS5's, KEF iQ70's. I'm not saying they would be better, just that'd be a starting point. Because I think the ATC SCM11's are probably the best sounding all round speaker below £1k, I'd fancy my chances that they'd do the trick, but they'd need a little more grunt than than the 752's demand.
I'm guessing you'd have to look at the £1k mark, or even a little more to replace them. I f I call correctly, they were around £500 when new, and back then you could get a good floorstander for £300, which are now roughly equivalent to what we have at £600/700.
As Rob mentions, a decently designed speaker stays the course, and even a 30 year old design can still be competitive today. Tajke the KEF Reference 104/2, the Jim Rogers JR149, various BBC based monitors, Quad electrostatics etc. Weirdly, all but the Quads are designed around KEF drivers.....that says something about KEF's past dominance and influence on the market in general.