Unless you are flying a lot on Thai, Thai ROP is not a great program (in terms of awards) The earn:burn ratios are, for most routes, worse than many other star alliance programs - worse even than Krisflyer. If you are after quickly earning star gold status - Aegean seems to be the choice of the moment, whilst there are other programs that may suit you depend on where you are flying most often and where you want to redeem most. Since BMI exited star alliance, there is no clear leader in star alliance frequent flyer programs and it really does depend on individual flying patterns and preferences.