I would LOVE to see Haibara x Conan. Buuuuut I don't think it's gonna hapen. The relationship is at standstill. There was no significant development in ages. Meanwhile Ran x Shinichi gets developed every 10 or so chapters. At this point the chances are slim to none. Which is unfortunate because for once I would like to see something else than childhood friends becoming a couple ( Heiji X Kazuha / Kaito X Aoko, do we really need 3 childhood pairs?)
I see it like this
Dream scenario: Haibara x Conan (chances are slim)
It may happen if: Ran dies (impossible), Ran stops loving Shinichi (pretty much impossible at this point), Shinichi stays kid because APTX can't be reversed (higly improbable and could be considered a spit in fans faces), Conan/Shinichi has change of heart (too late for that, we are 950 chapters in and no change of heart occured or was even implied). Conan obviously feels something towards Haibara. It may even be slight affection as he blushed while Ran assumed that he likes Haibara. But I think it's more of a protection bond. He failed to save her sister so he guards her.
Okay scenario: Haibara either dies or stays single (basically becomes female Agasa, partners with Shinichi ?).
I would be okay with this. Her dying is something that I could see. Sacrificing herself for Conan may be one of the options. Her staying alone I could also see. She could parter with Shinichi as his lab expert.
Worst scenario: Haibara stays a child and ends up with Mitsuhiko
I am not okay with this at all. Some people seem to like this ship. I find it atrocious. While I can see why some people would assume that the ship is good (Mitsuhiko is smart and caring) I still don't like. At all. First of all we have the fact that it's basically 18 year old woman and a child. Second I don't think Haibara is gonna stay in her kid form. I just don't see it. She's strong and independant. While she's a child she depends on too many people. Reliving bad childhood to be happy just doesn't seem like her character at all. And if this ship does happen I will be so pissed I'll probably end up writing pretty angry fan mail and sending it to Gosho.
PS. Even if Haibara x Conan won't happen I want to see them have a case as adults before the show ends. Maybe infiltrating some party or something like that. I want to see their chemistry as adults and all kinds of funny/interesting situations that could occur. Make it so Gosho!