To answer one of the original questions: yes, they are your only choice for direct flights from BKK. Bangkok Airways, IMO, is just fine. Their private airports down in Samui and up in Sukhothai are first rate relative to their surroundings, and their facilities at the Don Muang hub (BKK) are quite nice, including their departure lounge, available for all pax. Again, IMO, 'safety' in general is as good as, or better than, most US-based commuter airlines.