I do think having a national dex is something they should prioritize. It was kind of a downer to hear that I cannot bring all of my previous Pokemon into the game. My other complaints would be the Pokemon just popping-in in the wild areas (and there are some that don't really blend in well with the environment, like there was some footage with a Gyarados in water and its movements didn't seem to have any impact on the water), the NPCs still not being very lively, and lack of some modern touches like voice acting. With that being said though, I guess I am not quite as pessimistic about Pokemon Sword and Shield as a lot of others here have been. I feel like the wild area is a great step forward for the series and it does seem quite expansive. The customization features for the characters and being able to interact with Pokemon I think is well done. Dynamaxing looks interesting. Raid battles are a great feature to bring from Pokemon Go. I guess, I might be disconnected because a lot of fans disliked ORAS and Sun and Moon, but I really enjoyed them (despite their flaws, and lets be honest every game has flaws in the end). I see Sword and Shield particularly being held up in a negative light by some through comparisons with games like Breath of the Wild, as if those games did not have to make any compromises (in BoTW's case that amazing open world and its mechanics came at the expense of enemy variation, more traditional thematic dungeons, and even some story elements; and that game had a longer dev cycle than Sword and Shield).
I do not really blame the dev team for some of short-comings here. They are likely given a strict timetable for these games due to other media tie-ins, so I don't blame them for playing it safe. Honestly though, I would not mind the GameFreak taking a 2-3 year development cycle to work on the next game (especially since they have just gone through a major transition from 3DS to the Switch). I feel like that will give them much more time than they have been given to take the series forward. In fact, while they work things out, I would not mind to see others take a hand with developing Pokemon spinoffs (especially now that Pokemon Home will connect everything together). We have yet to see things like Mystery Dungeon and Pokemon Rumble on Switch, and I would love for Pokemon Company and Nintendo to allow Monolith Soft (provided they want to take on such a project) to develop a Pokemon spinoff in the same vein as Xenoblade (I feel that that series' battle system, especially the Xenoblade Chronicles 2 variant of it would work quite well for Pokemon); this would also given Game Freak more time to experiment and develop with less pressure.