salvadors

I currently have around 140k miles, and I'm trying to work out what to do with them, particularly as the general consensus seems to be that it's better to spend them sooner rather than later! (I've also a few other flights upcoming soon, and still have a full purchase allowance left if I need to push this up - 150k seems like the 'magic number' for several key options)

My current plan is a 7 or 8 month trip from mid/late September through to April/May next year. The only 'fixed' destination is mid-December to mid-Feb in New Zealand (and even that has some flexibility). The rest of the trip is still wide open, although I would like to travel around a bunch of the SE Asia countries, and if I can make it work I'd quite like to visit some friends in Japan (preferably after NZ, but before is also possible). I'm based in Estonia so would will probably be starting and finishing in Zone 2, although it's possible I'll need to go to Kyrgyzstan around the time I'd be starting anyway, so I might need to factor that in.

My plan is to do it all in business class (so that's what I'm using in my calculations), but if I were to end up with a bunch of spare miles I'd consider doing some of it in first.

My first thought was a RTW (150k+£1020), but although I'm quite happy to spend a few months in South America and/or some of the Pacific Islands, I don't necessarily need either a trans-Atlantic or trans-Pacific, so I started looking at alternatives.

A simple round-trip to NZ would be 150k miles with no top-up or 75k+£510, and booked as two singles would give me two stop-overs that I could presumably make a couple of months long each, and book some separate flights for traveling around during that time.

I'm assuming Tokyo isn't going to be a valid stop-over (is there any way of finding what options there are other than plugging destinations into the online calculator and seeing what routes they take?), but Z2->Z9->Z8->Z2 comes out at the same amount as a simple Z2->Z9 return, due to the cheaper Z8->Z2.

Presumably then I could make a Z7 stopover on the Z2->Z9 leg, maybe Australia on the NZ->Japan one, and somewhere else interesting between Tokyo and Z2. And I'd only have used half the miles of a RTW, so I could spend the rest on flights within zones 7, 8, and 9, or construct a more elaborate route (e.g. 2->10->9 isn't that much more than 2->9 and would give another stopover (CPH-BOM on EgyptAir seems to offer IST or CAI).

Are there any flaws or gotchas in building a trip like this? Anyone have interesting route suggestions? Any other threads here I should read on it?

Thanks for any ideas or pointers!

PS I only have a Silver Card, so don't get any of the Gold benefits. Not sure how important that might be, but thought I'd throw it in anyway.