I'm a bit confused as the request for information is a bit contradictory. You are not concerned with earning elite status but do want FF benefits!? Also, it appears you are more concerned with cost of this better seat.

That being said, go with the best deal probably based on season. Fly an all-business class discounted product such as SilverJet or L'Avion. Limited routes but good price. And then during off-peak business travel time such as Thanksgiving and Christmas, you will find a slew of commerical airlines offering heavily discounted business class fares.

For best comfort in Y, probably best are the English carriers - i.e. Virgin Atlantic (747s with Nintendo games and amenity kits in Y!), BA (3 choices of meal including vegetarian option) or lastly BMI (cheaper business class pricing and multiple mileage bonuses on these miles so easier to earn elite status faster).

Since most flights within Europe are so bad, it won't make much difference who you fly really as there is no real business class, just a blocked middle seat and a moveable curtain.