Well. For me it was the Ferrari years, partially because I did not really like Michael Schumacher, partially because of the suspicions around at the time, and partially because of the unrestricted nature of F1 at the time, testing, tyre development etc. some may say that it is what F1 should be all about, but driven by a huge spending bonanza, personally I prefer a more innovative environment.
My main gripe in many of these is that is not really the fault of the team who do well, it is the fault of the others, and then with the strictness of regulations, testing, caps to wind tunnel and CFD, the current rules bake in advantages, and a lot of the time the seasons turn in to a bitter political row.
I see this season slightly differently. I would argue that Ferrari should be right up there battling with Red Bull most weekends, but seem to contrive to throw it all away, whilst Red Bull are simply doing most things right. Yes the car is clearly a stonking one, but at this point of the season they are not under pressure in either championship, and can well afford to be relaxed about things. Now with Mercedes coming more in to the fray, it is only going to be easier for them.
Hopefully next season will see more teams at the front, with more stable regs, and the other teams learning from operational issues.
Also, I would add, how you feel about dominance may also depend on who you support