Hikari is one of the interesting characters that I don't overly prefer one shipping to another. My absolute favorite is definitely
2. Ikarishipping. DON'T ASK ME HOW I STARTED TO LIKE IT. Omg, I used to hate this ship with a passion, thinking it was utter crack, but then I started thinking and I see it. However, the fan base for this pairing seems to have no grasp of either Shinji or Hikari as characters, which still puts me off the ship somewhat.
3. Heattagshipping. Kouhei is awesome. 'Nuff said.
4. Penguinshipping. This is more one-sided, yeah, but I can't help but want to root for poor Kengo, because it's so obvious that he's been in love with Hikari all his life. He's a really simple guy which makes him a wholly boring character, but this scenario plays out more often in real life.
5. Cavaliershipping. idk, but I REALLY like this. I can think of Hikari as the girl who writes "Shigeru loves Hikari" on her notebooks and stuff like that, and she's infatuated with him because he's a poet and a researcher and a (mostly) better battler than Satoshi... Which makes her appear as a lovesick girl almost, but Shigeru would laugh it off as being cute and then be all romantic-like
The last four...I cannot go without my yuri <3
Numbers 1-5 I pretty much all like equally, LOL, except twinleaf a little more than the others..