i think the reason none of the captain have ever seen the king is cause the king is just to powerful,, like when renji tryed to look at Kuchiki Byakuya he only got a glimps but not a long enough look to real see him, u would need the power of the 1st captain
Im assuming that, their are multiple plateaus in this series now that the King's plane has been revealed.
The human world being the middle ground, and the Soul Society and the Hollow's plane being the sub-planes to Heaven and Hell, respectively.
what if the king is just a short old guy like the fairy tale guild master
If you really need another similarity between Ichigo, Isshin and the Shiba's, look at the way Isshin is always fighting, ehem training Ichigo and then look at Kukaku's training of Ganju. Seems like they grew up in the same house, huh?
Good theory on isshin, i mean according to what grand fisher said about ichigo being a "shinketsu/ true blood" shinigami could explain alot about why ichigo's power is so great. It would be nice if more were revealed about isshin's past, but kubo is probably saving that for later.
hmmm i doubt he is the king of soul society because why would he leave his own kingdom and ichigo not getting the much respect from out soul slayer because that would make him a prince
I also highly support the whole Kurosaki-Shiba linkage
The most a person can learn about Isshin is probably back in Volume 3 when Ichigo fights Grand Fischer.
It's totally obvious that the king is Jesus Christ. =P
But Isshin is defidentally not the king. He was a captain, hence the haori wrapped around his arm.