Although I occasionally ponder on what I'd buy if I suddenly became very wealthy, the truth is that I don't really have any great "I wish" bikes in mind.
I've no interest in carbon or in fast road bikes (or fast anything really), I don't much like the look of most modern bikes, and my current bikes suit me very well - in particular the Raleigh Royal tourer I built last year for £250 and the GT MTB I got for £110. I occasionally think that I might one day treat myself to a nice new tourer (and I could afford to buy one if I really wanted one), but then I think back on my most recent rides on the Raleigh (which I've got fitting me just about perfectly now) and I really can't think of what improvements I'd actually want over it.
I sometimes half regret having given away my first proper bike, an Ernie Clements Falcon. But I'd just bought a shiny new bike, and if I'd kept both then a friend who couldn't afford a bike wouldn't have had one at all - so I'm happy it was the right decision.
No, overall, I have to say I'm happy with what I've got and I'm really only interested in doing more rides rather than possessing more stuff.