The Griot's machine is still regarded as one of if not the best dual action machines. The trend during your absence has been longer throw DA's (Flex, Rupes and even the Griot's BOSS G15/G21 machines). However, in my opinion, the Griot's is the best of the remaining "regular" throws and still works perfectly fine for many.
Another trend especially for the traditional DA's is thinner pads. Thinner and smaller diameter pads means less mass for the shorter throw and counterweight rendering them more effective. My favorite for my PC (when I use it) are the Lake Country Thin Pro pads.
M105 and 205 are still effective and there remain loyal users. I was one but have moved on to others that simply behave better with regard to dusting, finish, wipe off etc. I like Menzerna and Sonax compounds and polishes.
I have been all over the new coatings for my daily drivers. I like the characteristic of durability, especially because I am too tied up doing customers and don't have a lot of time to get to mine. For me, coatings keep it looking better longer and washing is easier. If you don't want to mess with LSP's, you can coat it and carefully wash it for a year or more with a coating.
If it were me, I would probably give it a good wash, decon and M205 session, then coat it.
Now, having said all of that, I have a ton of customers that get my cleaner/sealant package and while it's a money maker for me they sacrifice durability. Yup, they are quick and effective but i'm old school in that I want full correction then very durable protection on my personal vehicles. My favorite has been HD Speed in that customer provided category but will be trying out Blackfire's offering soon. I've tried maybe 5-6 "AIO's" or cleaner wax/sealants to date. Speed works for me with customer's.