In your 'case' I would choose TG - just to 'stay' a little bit longer in Thailand mood (service attentivness).
For the miles and because of my upgrade possibilities as a LH Senator, for me, the LH (if LH would confirm my upgrade) connection through FRA would be then my first choice (if the additinal miles wouldn't get me over the over-all-mileage limit permitted (29'000/34'000/39'000).