Back then I went RTW on standard airhead road bikes, two up with camping gear (pre GS days). Quite a lot of the roads out side of Europe and north America were pretty rough, but a set of standard Craven panniers worked fine with only a little bit of remedial welding required in Ecquador. Australia included a lot of dirt roads, some rough. Spend your money on the toughest suspension you can find and does not mean Ohlins. Plus decent panniers. Modern tents are very lightweight and I still enjoy sleeping under canvas, even if I eat out.