These are just opinion, nothing more...

For sockets, I've done both, and both work great depending on starting point. If they are not in bad shape, I'll do the filing of the joint, and a bit of solder so they are solid. But if they are too gone, I'll just replace. I figure that I won't notice the cost after 6 months of play, and having lights that don't flicker is the only goal here. If I can get them solid with not too much effort, I'll do that, otherwise, I'll replace.

Use white. Again, just opinion. I love the stock look of fresh from the factory. And I will get closer to that if I use the color and type of post that came in the game originally. But if you like something different, by all means, do that. The greatest part about pinball is that if you are restoring your game, you get to do whatever you like. And don't ever let anyone tell you differently. Heck. if you like rainbow puke, do that too. It's your game, and the only one that needs to enjoy it is you.

Parts like tails and lockdown are a preference as well. I usually like the original, even when it has some wear on it. It's a connection to the history of the game for me. I love seeing the scratches and dents that were acquired over the years. It makes me feel the line of ownership of the game. But if you want to replace, go for it.

Obviously the overall important thing is to repair the game how you want it to be. I like original, but if you like different go for it. Either way, I find Stars to be a remarkable game. Mine is restored how I like it, which is original, and playing great. I suppose if I had a new playfield, I'd have done that as well. Enjoy the game when you're done.