On the other hand, Finland and Sweden are so similar nowadays I think a political union might result in quite a small differences to OTL (such as common currency). Finland would benefit from better legal system (laws in OTL are copied and translated from Sweden, but Finnish judges are more corrupted) and better health care...
Finnish judges being more corrupted? WTF? I'm pretty sure that judges in both countries are corrupted in pretty equal degree, that degree mostly being "not at all."
Also, I don't think that Swedish health care system is any significant way better than the Finnish one.
But yeah, Sweden and Finland are pretty similar, and a political union wouldn't probably change things much.