If you are sure you won't want to try 11 channels in the next few years, then the 2080 is just as good, but are you really sure? I went from 11 channel to 7 channel for less than two weeks and then back to 11 channel, though I am still just using 7 channels, for now..
The 3080 does have a better DAC chip but I highly doubt the overall difference is audible, especially now the 2080 is fitted with the ES9007. I can't find the data sheet for the ES9007 but I would imagine it should be a little better than the 2070's ES9006.