I too still have G system that I use. I stepped up to it from a nova system. I think the G major 2 is pretty close in terms of effects to the G system and could be used the same way with a midi controller. The effects are still great sounding and do everything I need. Much better than the built in effects in my H&K grandmeister. Some of the advanced effects are limited but it’s got all the basics down and they can be switched on or off separately from switching between presets.
I wish it had some looping ability and the midi implementation is weak. I would have liked a different midi cc for each preset programmed to a switch. I solved this by using the relay switching instead which allows me to toggle between channels in a preset. If it had a few more buttons that were programmable it would be great. Considering it was last updated in 2011, it still sounds light years ahead of most pedalboards. If you need boutique effects that are out there it won’t work but for a great chorus, delay, reverb, phase, eq, noise gate, etc. it does the job well.
There is quite a learning curve and I spent a lot of time reading about set up and building my own cables and rack panels for my custom set up. I’m sure the curve for setting up a digital system like a kemper is just as steep. The price for the tc systems has dropped dramatically too so it can get you a good setup on a budget.