Hey guys, thanks for the info and advice.

I would surely love to go see my local timber framing engineer, but there isnt one in this country. We have a guy who does our engineering, but he's a normal civil construction engineer who has done some work to get the maths for our joinery and is happy for us to build frames our way and sign them off for the bureaucrats.

We laid the first bent out this weekend and put all the old joints together to have a look. It looks like most of the original holes have actually held up fine, and I re-pegged one post/beam/brace connection which worked fine.

I have definitely gotten a little gun shy after your thoughts above though, and we will examine each joint and do one of 4 things depending on how it looks when it goes back together.
- if everything looks fine, we'll repeg with original small sized drawbored pegs, and then add a larger peg between the two provided the tenon is wide enough to accommodate it.
- If the joint needs support, we will add either a steel plate on the outside of the connection, or rout in a bolt to tie the joint together.
- If the joint is too far gone we will replace tenons with splines or renew mortises with timber blocks replacing cut out sections.

From the looks of it, 90% of the frame will be done with method 1, and we can take the time to make sure the damaged joints are redone properly.

I'm not sure how to get photos on here just yet, but when i work it out, ill post some pics of the original condition, and parts as they come back together.
As for timber, its called Callitris, and is a native Australian timber. It's called Native Cypress, but its not related in any way. It does work a bit like Cypress Macrocarpa though, but is harder, very durable, and termite resistant. It's got some real funny properties when you work with it, the best way i can describe it, is that it feels Crispy under a blade.