Most UR generals really aren't that useful. You'll end up needing to use a bunch of UR or Universal EVO cards to rank them up to four stars, and those come slowly, to say the least. So you basically have to pick the one that you think is the strongest that you have or will have anytime remotely soon as the one to use your UR and Universal EVO cards on.

As a survey of sorts of what the top tier players are using, at least in PVE, I checked the recent victories on the seventh opponent of map 6-4. This has the advantage that only six players have beaten it, ever: Temp, Semaphore, Nootaku, Aargaez, Vermillion, and Arikromus. All daimyos in the past 2+ months have come from that list. With only six players having beaten the opponent at all, it retains the first victory by each of those six players rather than getting scrolled off. It's also a not terribly difficult opponent, as the enemy is all elite guards, so you don't get people pulling out weird tricks to try to customize something for that particular opponent.

So I tallied up the generals used, including both the base generals and also the inherited ones. The totals are:

UR The Dragon of Echigo: 1
UR The Tiger of Kai: 8
UR Master Strategist: 2
UR Sanada Yukimura (S): 1
SSR Uesugi Kenshin: 1
SSR Toyotomi Hideyoshi: 2
SSR Takenaka Hanbei: 3
SSR Mori Motonari: 5
SSR Miyamoto Musashi: 1
SSR Sasaki Kojiro: 1
SSR Kamiizumi Nobutsuna: 2
SSR Honda Tadakatsu: 1
SSR Honganji Kennyo: 1
SSR Sanada Yukitaka: 5
SSR Takeda Shingen of Kai: 6
SSR Toyotomi Hideyoshi (S): 3
SR Naoe Kagetsuna: 6
SR Katakura Kojuuro: 2
SR Date Nami: 1
SR Yagyu Munetoshi: 1
SR Imagawa Yoshimoto: 1
SR Honganji Kennyo: 3
SR Otomo Yoshishige: 1
SR Ashikaga Yoshiaki: 2

That's more SR than UR, and from a set of players who could easily go exclusively SSR if so inclined. It's also more SR Naoe Kagetsuna alone than all UR besides Tiger of Kai combined.

If you were to get a more PVP focused survey by counting the generals used in the quarterfinals of the daimyo tournament, you'll see a lot more SSR Uesugi Kenshin, SSR Takenaka Hanbei, and SSR Sasaki Kojiro, but not more UR generals. You pick your favorite, evolve your favorite, and won't get around to evolving your second favorite unless you play for a number of months.