I'll list out the Lions team I think Gatland will start (Not necessarily the team I'd start) because I'm guessing a few people on here might be interested in predicted line-ups:
1. Wyn Jones (South Africa are going to destroy him in the scrum and there are better scrummagers around but this is Gatland after all)
2. Ken Owens
3. Tadhg Furlong
4. Maro Itoje
5. Alun Wyn Jones (c) (I think James Ryan is the better player right now but again, this is Gatland we are talking about)
6. Tom Curry (Hard to pick this one as Curry is better suited to 7; I think it should be either Curry or Beirne but Gatland might include Tipuric or Navidi)
7. Hamish Watson
8. Taulupe Faletau
9. Ali Price (Weakest position within the Lions' squad)
10. Dan Biggar (Might be Farrell instead but hard to know at this stage so went for the Welsh player)
11. Anthony Watson (Gatland might go for Josh Adams or Liam Williams here)
12. Robbie Henshaw
13. Jonathan Davies (Ringrose might be a better shout here but think Gatland will go for Davies)
14. Louis Rees-Zammit
15. Stuart Hogg
There's a lot of tight calls but I'd go with most of your XV except Beirne pushes at 6, Murray at 9 (not an easy call at 9, Davies? Mehh).
Last time, I thought Gatland not only went for Wales players when it was 50/50 (fine ... go with the player you know?) but some who were 45/55.
As not coaching Wales any more, I think he picks vast majority of this squad regardless of nationality and the Welsh players that get in the squad do so on merit... the starting XV is another matter but I don't think it really matters. It's a squad game nowadays anyway and even more so on a Lion's tour. I think it was Woodward recently who said he had a XV in his head pre-tour and because of form and injuries, only 2 played in the last Test. When you add the opponent (and the likely hits/injuries) on top, they'll use 25-30, maybe >30, in the Tests?
* Wyn Jones gets in the XV on form
* Owens cert
* AWJ gets in squad easily and the XV
* Tipuric goes but a lot of competition there? Really impressed by Watson, especially going forward, ball in hand
* Navidi has had a good tournament, will go (not sure if in the XV though)
* Biggar def deserves place in squad and between him and Farrell (playing well, can cover FB if Hogg and Williams get injured) and aerial game is brilliant but 10 (and maybe 6/7) have so many top options .. Sexton, Farrell, Russell too? Farrell will go (plays 12 also), so Sexton or Russell miss out. Ouch.
* Liam Williams goes on form (and can play two positions well) but not sure he makes the XV
* JD cert
* RZ goes (can double up as schoolboy mascot)... before Josh Adam's stupidly broke CV rules, you'd have got long odds on RZ making the tour, never mind starting a Test.
Could see 7 Welsh in first Test.
Shame we can't pick one French player, Dupont walks in.