Well BOS being developed by the same folks that did ROF, it does have some similarities, but also has some differences as well. Based on the info you have provided, I would be inclined to think you would probably like BOS better than Cliffs of Dover.
You did not mention whether your interest was more in MP or SP.
If you compare the SP mode of BOS to ROF, be aware there are some significant differences. Many think they are big shortcomings. The stock campaign that comes with BOS, is not like your typical SP campaign from sims past. Certainly not even like ROF's campaign, or it's career mode. It is more of a groundhog day type of campaign, where one earns level ups and skin unlocks ( for the premium version, for the standard version also equipment unlocks). Buyers of the Premium version can unlock all equipment unlocks by pressing a button to unlock them. They added that option for the Premium buyers after all the pushback on this system when it was released, primarily from the MP crowd.
Now there also is PWCG for BOS, don't know if you ever used this excellent campaign generator from Pat Wilson for ROF, but he has now done it for BOS as well - mainly do to the desire for something better than the stock campaign type system. So for the SP community there is something much better now, for those that desire more of a traditional style of campaign system.
So I would say if you are pretty happy with ROF, you would be happy with BOS, just be aware that it is not quite the same. It does have Normal and Expert play settings, and in the Normal which is pretty simple, one can go in and turn on individual settings to customize it somewhere between Normal and Expert.
It also does not have quite as extensive a controller setup menu or graphics setup menu as ROF has, more of a simpler approach to these selections.
Also flying the planes, does take some learning and getting use to the individual planes. But if you are used to ROF you are probably already familiar with that aspect.
Good luck,