Cambodia itinerary... Help!

If you are insistent on taking a pass take the second one, this will give you time to yourself and allow you build up some confidence of sorting stuff yourself. Asia is a very different animal to NZ or Aus, it is also very cheap to travel, you will find that you could do it for a fraction of the price if you did it yourself. Cambodia is very easy to get around on local buses, no need to be afraid, there will be plenty of other travelers wanting to chat. by doing it yourself you don't have to compromise on anything and will be able to see all you want to.

Thanks for your advice, I am leaning towards the second pass as I want to be able to relax and not be too pushed for time. I understand that it would be easy to get around on local transport, it's an option that I have looked into and if I was traveling with a friend it would definitely be the way I'd do it. But I've found it hard to meet people by myself in the past, groups together often aren't open to approaching lone travelers, and I'm not great at approaching people I don't know. It takes me a while to feel comfortable around new people which is why these buses work for me, even if they aren't the best option travel wise. I'd rather miss a few sights and make some new friends to have fun with, than see absolutely everything but find myself somewhat lonely.

There's also another pass option which includes Kompong Thom and the national park, but misses out a homestay and Bamboo Train ride in Battambang, would anyone recommend one place over the other, and why?

One thing with Stray, you may be locked into a route but you can be totally flexible with the timetable. Plus you arent travelling with the same people every day.

Why would any person bother with a Bus Pass ,when fares are a pittance in Cambodia.
Siem Reap to Phnom Penh from $6 to BAttambang from $5
Stray are asking $693 for a 11 day Pass
My advice to you is to only travel in a full sized Bus.

OP has said why they are tending towards this sort of pass. Its obviously NOT for the money. If Stray is as well run in SEA it is in NZ, then OP will have a good time.

When I looked at the timetable link, it seemed that a lot of the routes in those packages only run twice a week, which seems restrictive, unless I am mixed up.

Thanks for all your responses, I understand a lot of people won't understand wanting to travel on a bus pass when public transport is so cheap, but it's the way I feel comfortable doing it alone, and if it's a choice between not traveling at all and doing this way, surely it's better to do it this way, even if it is more expensive and not as authentic? I have looked at doing a full blown tour as well but I've done these before and there's too much rushing around and not enough time to do your own thing. I feel like these buses are a good compromise for me.

Could anyone please shed some light on my questions above, Kompong Thom vs Battambang, and any opportunities for hiking/trekking along the above route?

As a Kiwi, I'm glad if you had to pick a company, you picked a well known and reliable NZ one.

I would pick Battambang over K. Thom as there is more to do and see, its a chilled out small city with plenty of riverside bars and some good sights to see nearby. K.Thom has the very interesting Sambor Prei Kuk and the moto ride out there is cool, however you can do similar things in Siem Reap and obviously Angkor Wat is more impressive. For Trekking you are better off in the Cardamoms or Mondulkiri however I think there are some companies doing treks around Siem Reap although not as remote. Google the Mekong Discovery Trail.

I did the Kiwi Experience several years ago as I had just been months in the outback on my own and wanted some social, it worked perfectly, lots of new friends and booze and no responsibility, I enjoyed it but wouldn't do it again, I do understand why you want to go that way. I also see many people on here thinking how much further they can go on the same money.