Hi,
I use a 12' dob from bintel and extremely happy with it. Personally I would go for the biggest aperture you can afford keeping in mind weight and portability. Just the ota on mine weighs in at around 20kg, can be a little awkward especially packing up late at night when your tired. With the collimator I purchased a simple orion chershire one from bintel to get me going, there has been a fair bit of discussion about what is the best laser collimator on the equipment forums. If you purchase a cheap laser it seems that they aren't aligned real well and they don't project a dot rather a small line or a sausage, im still looking into this one myself. I don't own a Barlow yet so can't help you on that one but with the eyepieces Ive got the stock standard ones that came with the scope 32, 15, 9mm they provide a good selection but ive also bought a Meade wide angle 25mm slightly higher mag than the 32mm but a clearer image. Hope that is of some help
Cheers
Scott
