I like the new interface. It feels closer to other DAWs and has similar color values to the Adobe CS6/CC products that I use everyday. Real faders and workflow enhancements abound. So far, so good. I'm still really digging in and exploring but the new MIDI FX brings it closer to some things I'm used to in Live 9, even though I do use them in tandem.
I had no problems with spending another $200 for this version because, well, that price is dwarfed by what I pay for upgrades to all of my other software. It's not the biggest update possible but what was improved, while not life changing, are welcomed and indeed improvements.
There are a few things that do bother me, like how small the faders are, how fiddly the mixer can be and some of the older instruments looking garish when compared to the new interface. I also do not like that when naming channels Logic doesn't continue playback but instead starts over. However, my opinion so far is mostly positive.