Yes, there is no one easy answer. Here are three screen shots two using a 4 column grid and the other with a 2 column grid. Each as a different theme.

It would seem that having the top of title, images and add to cart button all lining up would be graphically pleasing. Seems that your suggestion of limiting all titles to 1 line or two lines would be an answer.

So many words on a line and that is it. If it breaks improperly then edit the text as it is hard to tell when a line break will ocure. Something like a max length in a form field text box. A help, but not 100% as longer words would tend to not break.

Overall, the grid works nice with a lot of control. Now to just train my site editors to not get too carried away with titles. Only so many words that must fit on exactly two lines - not one - not three - but two......

Jim