Try Yacreader - http://www.yacreader.com/
I moved to it a few months back and haven't looked back. I've not used it yet to download info from Comic Vine but it is possible.
I did have an issue using version 7.0 on Windows 8.1 but just used an older version and it worked fine but this may have been fixed since.
I'd like a comic book reader with a library system, similar to yacreader (I can't seem to get it installed on fedora). Maybe with pdf and ebook compatibility too would be neat.
I use YACReader Portable. I used to use CDisplayEx, but it was prone to crashing. SourceForge is not really the best site to be using.
I haven't tried any myself because I'm not personally up on comics, but I know there are Mac comic readers which essentially are for comics what iTunes is for music. This one seems pretty extensive, this one is more minimal. If you stick with one of them, make sure it's set up to store your library on the external disk similar to iTunes.