You do realise that often stop-overs are not allowed on award tickets? - e.g. with SAS Eurobonus stopovers are not allowed. For TK M&S and LH M&M 1 stopover is allowed for return tickets. Besides, South America may not be in the same award zone as Mexico (depends on your FFP) and then it becomes a much more expensive 3-region award.

Yes, Bogota is a very nice place to spend a few days (you will like the price levels compared to Sweden!) I was there/in CO for the first time in July - I want to go back!

Avianca: hard product is good on the B788 which are used for LHR, MUC, MAD (and BCN?) but the soft product/service is poor in my opinion (based on flying GRU-BOG-GRU in C in in July and domestic flights - it may be different for real longhaul flights).

I like the efficiency and often very good connections with LH. Hard product and soft product is decent/good, but nothing spectacular. Meals/food are much better on TK. You really can't go wrong with LH but watch out for taxes, surcharges, YQ that need to be paid for LH group flights when on award tickets.