hey coolcoil
1&2) Do a search for miranda.mario. It is an AV elite on FT that frequently complains about AV/TA upgrades. I have also complained about my upgrade mechanism, it simply doesn't work. AV IT is AV IT after all.
3) I never flew LACSA but my experience with TACA were so positive that I felt it was a shame that they had merged with AV as they would invariably drag down their service levels. A Salvadorean crew is at least for the time being far superior to a Colombian crew. They seemed to ooze courtesy and professionalism. On the downside TA A319s do not have the IFE that AV has
4) I love SAL, it is tiny, there is a bit of pointless security theatre to get on a US bound flight there but you should probably complain to the USA about that.
5) I didn't know El Salvador had a yellow fever requirement, but FYI you can get this free at BOG to the left of international check in opposite the ATMs
6) Dunno, I have not been to the lounge, but there is a great little bar, cheap prices and they take USD