Weathered Warrior 3 is a better Lucky Skill due to powering up Moves and Sync Moves. Critical Strike 2 is good if you're on a budget and Surging Sand 3 is good if you care not for the Sync Nuke.
Silver is a very good rock type unit but that is not difficult but he is miles behind the best master fairs in the game. It is good that we have a good rock type in the game now but he is not that impressive. He does not dominate the entire game like Ash and Red.
Using both on a team is so much fun. They're ridiculous. But comparing the 2, Geeta is way better. Her damage output is better and she has a rock move that attacks ever turn and to all opponents(both 1/5 move power) Geeta is the best I've seen, she is o.p. I love shiny champion Silver too thou.
While he is a good Rock Type Striker unit, he's far from good compare to other Top MasterFair Strikers. There are things that I found that have issues with him but you can disagree with me if you want; - We don't have a good Rock Support who can summon Sandstorm to help synergies with Rock Types especially with gauge(Ingo is Ground type yet outdated, Lodge Raihan only works on entry with low Def stats and Paulo is a Sprint unit with also low Def stats.) - There is less Johto unit who can synergies with him as of now, (SS Morty can synergies with OG Silver, OG Ethan and OG Lyra using Sun; SS Kris can synergies with SS Ethan, Eusine and Variety Lyra using Rain. You can try to work with SS Gio but it's way too gauge hungry so NC Silver is a pair on its own.) In terms of dmg, he's likely above NC Nate but that's it however NC Nate has a lot of Unova pairs who can work with him even using Unova Passion and Dragon Zone to utilize it(OG Iris, Champion Iris, SS Hilda etc;.)