I'm not sure where the complaints about customization are coming from, or the difficulty of use. With everything in life, you've got to learn the basics before things will start to make sense.
I've been creating my own sites from scratch since 1995 when I was introduced to HTML, built many sites coding in wordpad or sublime using HTML, FLASH and CSS - you could say I'm experienced. Then I started seeing these really amazing sites and I saw people updating them quickly, and alas, I discovered wordpress.
I purchased other themes and learned how to use when, when I converted over to a wordpress theme (vs building html files in sublime/notepad/dreamweaver and uploading via ftp). The other templates I purchased lagged beyond belief and almost made me go back to HTML.
One day I discovered THE GEM, and haven't looked back since. You've got to take the time to learn the template and how you build pages in it, it won't be like every other template. Sure, you're a great driver and can drive your car, but before you can drive an suv or truck, you have to get used to it right? I did the same with this theme, and it has increased my effiency two fold, and I'm able to publish pages quickly with the formatting I need. Even better, the author added GEM BLOCKS which greatly enhance your work flow, speeding everything up by importing a block and customizing it how you want.
Sure, THE GEM isn't perfect, nothing ever is, but this is the one theme I landed on and its here to stay. I know after all my time using it, I still haven't utilized and/or customized every feature available. But, my clients and my friends always look at my site and say WOW, this is a really professional site.
My advice to anyone who is interested in this theme, or already has it and is having difficulty, is just take your time to learn it. It won't be 100% perfect, but its really amazing compared to the other themes I have purchased and used, and my site never lags. Well done author!