G'Day mate and welcome to my swag, awesome site with heaps of info, search for jayco mods mate and u will be amazed.
I have an OB Swanny and the wife, kids and myself love it.
My 2 bobs worth, sounds like your keen on some off road type travel and camping ??, if so please dont think that you will be able to traverse the more difficult tracks etc with ur jayco, some will disagree, and each to there own, but IMO its not for heavy 4wd, light stuff no probs, the odd bit of difficult stuff also no probs, but defo not for prolonged travel on heavy stuff, food for thought, just my opinon.
If i had my time again, and was able to sweet talk my lovely wife around, i would go a decent hard floor camper, i think it provides the best of both worlds.
On the ext draw bar, defo go for it, i dont have one, and only have a tight space to store her, the added monouverabilty would be a real asset, also allows to locate a stone guard without to much trouble.
Sounds like you have the awning stuff sorted by now.
Only my thought mate, again welcome.