Hi there !
Just a quick message to say that your template is great !
But … !
As a photographer, it happends many times to have landscape and portrait in a same portfolio, or theme, and I’d like to suggest you another kind of horizontal gallery, like this one : http://demo.cosmothemes.com/tripod-colored/gallery/sed-at-ligula-at-ipsum-bibendum-mollis-id/
There is already in your theme a “vertical” gallery called fullwidth-image-side-content-gallery where you can mix landscape and portrait at full size without crop or blank spaces but the horizontal version is very interesting too in my opinion.
I know it’s a very hard job you have already done, but this type of gallery is great because you can mix easily landscape and portrait photos, without having blank spaces around vertical photos.
Thank you so much for your suggestion. We really love to hear feedback to our theme, and of course we always learn more from our customer to make better theme based on customer needs. We will consider to add feature like you mention above in future update.