Blue eyes will always go over far better than fake colours. I'm absolutely average looking and middle aged, and still get positive comments on it. As with my pasty British skin. I think the current standard of Japanese beauty favours north Europeans.
Japanese friends are a genuinely difficult thing. Myself, and a lot of foreign friends, as well as a lot of people I've known online, only really manage acquaintances. My ex-girlfriends are actual friends, but people without the sex relationship? I wouldn't consider any non-girlfriend I've known here as a proper friend, sad as it sounds. I don't want to speak for others, but it's a little depressing to me personally. To be fair, age is a factor, as I came near age 30, and people tend not to make deep friendships the longer life goes on.
Japanese men are less aggressive than Westerners on the whole, but I'm sure in Tokyo there will be many many alpha dudes who approach you there. I've seen them, and they creep me out way more than pick-up artists in the West, since they seem to prey on the politeness of Japanese (i.e., in N. America, it would simply be called harassment). They may not be the types you want to have a relationship with. I don't know what you are looking for in a partner. Go to good clubs, have a smile and a welcoming look, and say hi to people you find interesting, and you should do fine.