>>55693133while I agree that the layout of Unova is really boring especially compared to what came before, that really has very little to do with exploration and the expansiveness of routes. Hoenn/Sinnoh for example have more complex, interconnected region designs, but you still progress through them fairly linearly and the games rarely offer you a chance to freely explore the map. It does make backtracking more compelling and give more flavour to the region, but yeah I don't see what it has to do with exploration or choices. Kanto & Johto are arguably the only regions from this era with any significant choices.
Now, on the topic of BW's actual route design, I think it goes both ways. The design philosophy is a mixture of Kanto style short, compact urban routes for the main progression paths, but then also the more complex, exploratory design of gen3/4, it's just that the latter is usually optional now. So you can get through most of the map on a linear path with fairly few obstacles, but if you want to explore off the beaten path that option is available to you, and those optional areas are some of the most complex and sprawling in the series.