If fact you have 6 different ipdf versions to choose from, two of them are "column view" ones. Check the official thread:
https://www.mobileread.com/forums/showthread.php?t=22152
These versions are just modified versions from the official one so the interface is the same and also the functionalities, except for the additions, which usually change the behaviour of short/long button presses. Refer to the thread I mention and the links to the modified versions there.
I usually switch between a full screen capable version for "normal" pdf reading and a column mode one for magazine articles and papers reading.
In respect to the comic viewer you usually have comics in either pdf or cbr format. With pdf you are on the best side as you can zoom to the printed area, go to full screen (a mode in which the lower icons are hidden and the document fills all the screen area), and start reading. The zoom is kept between page changes so there you go :-)
If you have cbr's, you need either somehow convert to pdf (probably just a little script if you are in linux) or use an adecuate reader as iViewer
https://www.mobileread.com/forums/showthread.php?t=32915 (mmm as I was looking for the iViewer thread I found another thread which seems to talk about a cbr->pdf conversion tool, check it out
https://www.mobileread.com/forums/showthread.php?t=9125 ). iViewer doesn't have zoom, so if you have white margins bad thing.
Don't forget to install FBReader if you want to read chm etal
https://www.mobileread.com/forums/showthread.php?t=20490
Enjoy!