While I would love to see Felix again, it just wouldn't work because of the continuity issues.

Why? Why should every Bond film ever made have to harmonize with every one of its predecessors? If the franchise lasts for another fifty years, will Bond continue to remember his wife, a century after her death? In 2062, will he remember meeting Felix in 1962? Please. They'll have to dump the conceit of continuity eventually. I'd rather they do it sooner than later.
Had they adapted each book faithfully,
in chronological order, and with the same actor playing each part for the entire duration of the series, one could potentially argue that the films occurred in a strict Star Trek-style canon. But they haven't adapted them that way. Bond has gone
way beyond that point, into the realm of Superman and other "ageless" characters. So why should we continue to expect Bond plots to adhere to the same rigid rules, recognizing forty year-old events as though they happened recently? Why limit ourselves to contrived, inferior adaptations for the sake of maintaining some imaginary continuity?
I say we just enjoy each film (or string of films) as a self-contained "take" on the life of James Bond. On the one hand, it's not unreasonable to expect continuity within a single
era (for example, you expect Pierce's films to not contradict themselves), but to me it seems ludicrous to expect long-term continuity, such as between Connery and Craig. When a new actor is hired, his slate should be wiped clean. Otherwise, we end up with loads of unnecessary baggage that doesn't contribute at all to the fun. And the
primary object should always be fun, i.e. Felix.
Incidentally, I don't know where people have gotten the idea that CR is going to be a "prequel", like Star Wars Episodes I-III, but it seems like a major misconception. I believe Campbell explicitly stated that it would be a "reimagining". In other words, it isn't
supposed to agree with previous Bond films. It doesn't "come before Dr. No". It doesn't have anything to do with the previous film series, except that both are based on a character created by Ian Fleming, both are produced by the same company, and both will incorporate similar stylistic elements (e.g. the gun barrel, PTS, "Bond, James Bond", etc.)