Thankfully there is a more portable choice in camera gear that isn't Full Frame (whatever that is supposed to mean), 35mm format & mirrorless with all the announcements around now.
At Photokina Olympus reinforced their commitment to the Micro Four Thirds system being the ideal size format for portability & sufficiently good results, not to mention all the great features they offer in it. Next year is their big year being their 100 year anniversary. Rumours are (at least from one particular source) they will bring an E-M1 Mk III with much improved low light performance & higher ISO range, an MC20 2.0 times teleconverter & a PEN-F Mk II (at least in Japan to start with) all to come around March 2019. Also they will (says this source) announce a 150-400mm F4.0-5.6 lens to come at the end of 2019 (as planned). I assume (& would expect) it will have Sync IS as well.

Anyhow, there will be those getting into one of the FF mirrorless offerings now or next year but I feel that the FF format suddenly became saturated with (5 ?) different manufacturers bringing their version of a FF mirrorless camera. At least there will be choice, I guess. And thankfully also a choice that doesn't require a pack horse to carry it.