This is where I land on the subject for the most part (possibly less on the HATE factor). I am a fan of the history of the comic medium and the provenance of the art adds interest and intrigue to me. Plus, anything done to alter it almost always looks worse than leaving it alone and casts question onto why it was done.
For anything published, I say leave it as is with the exception of restoring a word balloon, etc. I have a few pages with balloon issues and I haven’t done anything because I don’t trust myself to do it … and getting it replaced is not a high priority to me.
I have seen a few commissions/sketches that the artist did on wonky sized paper – maybe a scrap, an odd-sized piece of paper, etc. that I think might benefit by being balanced (art/page) but I just can’t bring myself to cut up art in any way. Cutting art to fit a portfolio falls squarely into the category of “Not a good reason to do it” and the points of disclosing this when selling it a good one.
Speaking of cutting art, there is an ironic dichotomy in how I perceive cutting up a production page – I hate it if done outside of the production process (ie by a collector, etc.) but I find it fascinating to see how/why it was done by the artist/production team when it was being created for the comic. I own a lot of Sal Buscema pages and many of them are considerably smaller than 11x17 due to them being trimmed during the production process (I presume). Weird curved slices off the top, trimmed edges all around, etc. really makes me curious as to when/how/why it was done. So, if Joe Blow cuts up the art I am outraged but if Joe Sinnott does it – that’s awesome!