If if you're building a full blown CMS, there are several considerations to drive your decision, but for me, in general, once I started using Twig a few years ago in my CI apps, I haven't looked back. I reached a point that there isn't anything I can't do inside a template, although it didn't happen over night. It's an easy language/syntax to learn, keeps views super clean ( and almost always fewer lines, less code), and I find it easier to set up templates, load dynamic partials, etc. that with CI views.
We use Twig for every CI project we build. If I can help someone with anything specific, please let me know.
I encourage you to commit to trying it for at least a few days and see if it doesn't click.
