Part of the problem of a spread out pack seems to be the rules - if building a better mousetrap wasn't limited by having to make the engine capable of lasting several races, having to manage on a limited amount of fuel, having to get the bike to work with spec tyres and having next to no testing with contracted riders, I think that the manufacturers could be closer. I agree that most years there has been one machine + rider combo that is outstanding, and often one bike that appears to be the best to be on. Also I realise that it's difficult in today's straitened times for the manufacturers to put the money into development needed if one manufacturer strides ahead.
I still think (and have bleated on here about it often enough) that removing the fuel limit and the testing limits (as someone pointed out recently, the team still test so no money saved, it's just that they are not allowed to use their most valuable asset to do so. An equivalent would be only allowing tests with production engines - not cheaper, but ultimately not helpful in improving the bike.
I have been watching since 1987 and do not want the prototype class dumbed down any more than it has, IMO, already been by stuff listed above and more. I don't find the racing boring, nor do I need the top class to produce races like the stunning Moto2 from Aragon (I'd not complain if it did though). Whilst I'd love a return to the 2-strokes, 990's produced some of the closest racing before these rules were dreamed up.
As many have said, being the top class and the best riders provides its own fascination. I do however, question the changes that have been forced on the series in the name of safety and money saving. I doubt that either the engine rule, the testing rule or the fuel limit have saved anyone any money - more likely they have increased costs.
I know that Rossi and Ducati are struggling at the moment, but that is not my reason for disliking those rules - I was bitching about them in 2009, so no muppeteering here