get as much significant out-of-cast cr as your character can handle

try to integrate those characters with your cast. introduce them to the other cast members, bring them along to parties, don't give your cast members an easy way to escape tagging them but at the same time try not to be obnoxious about it...basically treat the out-of-cast characters like your new boyfriend you're trying to introduce to your friends. you want them to meet and get along.

then as plots go on be like "oh hey, my dude is in good with this other guy, he can help with this plot" or "my girl has found that she works really well with this other character, maybe they can tag along" or something. just roll with the flow.