I've only read the OP and nothing else, but here's what I found when I lived there.
Fife is an OK place to live if you're happy to use it as a platform to get to other places. As a place to live in its own right it's pretty mediocre.
Housing is cheap to rent, especially if you're happy with a pebbledash jockbox. You can get something really quite nice out in the sticks.
You can be in the highlands very quickly with the motorway, it's a straight forward drive. You also have Edinburgh, Dundee and Perth in very easy reach.
Some of the villages, particularly in the East Neuk, are beautiful. I lived in Pittenweem for a bit and it was very pretty (bloomin' cold right on the harbour side though!). St Andrews is good for a day out (but can drive you absolutely mad if you're there too long).
The weather is cracking- it's very dry for the UK and Dundee is the sunniest place in Scotland. It rains surprisingly little.
The riding is poor- the Lomond Hills and Pitmedden aren't too bad, but not thrilling and that's probably the best in the area. You'll cope in an "I've got no alternative" way but in the last year I lived up there I rode from my doorstep maybe 10 times and drove to ride elsewhere the rest of the time. If you can road bike there is a good scene, but the constant gale force headwinds are demoralizing. There are no hills worth speaking of.
Most of the towns are grim. Kirkcaldy in particular is very unpleasant, I've got some rough stories from when I worked there. While the East Neuk is pretty the major towns of Kirkcaldy, Glenrothes and Inverkeithing are industrial/dock/coal mining towns that are rather bleak.
There's not a lot to do. If your wife thought Dalgety Bay was dull the rest of Fife won't offer anything extra beyond the Scottish deer centre. Most of the days out that I can remember were out of town in Edinburgh, the Highlands, the Trossachs or in Perth and Stirling.
All in, it's a nice enough place but when I lived there I always wondered how people who weren't born there ended up living there rather than pretty much anywhere else on the east coast.
On the not driving front, before I moved back to nasty ol' England (it's worth noting that Fife is still better than being down here) I jacked it in and moved to Edinburgh and commuted to wherever I was working in Fife. The trains are either slow or don't stop at every stop, so if you do choose to live there make sure you're on the mainline at one of the well served stops.
Stirling is probably a pretty good bet, as is Perth though that may be too far.