Yes and also, it seems that it is not something new nor is it something strange anymore about the many players who will play in the Saudi Professional League next season. Big pay without a hard target to win the title, so it looks like it will be a comfortable task to undertake to play in the Saudi Professional League. But yes, even though it is rumored that there will be many players who will join, the reality is that there are still some players who reject it and still choose to play for clubs that play in Europe.
The fact is like that, especially the players who are still young. Surely most of these players will prefer to play in Europe. Because they will definitely think about their career for a longer time, and for a better playing experience. Because it is undeniable that the quality of football in Europe is indeed very good so far. Whether in terms of coaching or in terms of facilities and player quality, the leagues in European countries are indeed the best.For the time being, it will definitely stay that way.
But that doesn't mean that all of that will rule out the possibility, that there won't be young players who want to play in the Saudi pro league. Because if the Saudi Arabian League remains consistent, it wants to advance and popularize its football league. For the next few years, maybe there will be more young players who will be willing to play in the Arab league.
I just believe they continue like this, within a few years, they league will be top five league in the world. They have go facilities and good player welfare
While I agree that this league is improving really fast in these last couple of years,until this reaches a good European level it will take at least another 2-3 decades before they become competitive.They have facilities,modern ones,a lot of money and this if used well and managed well can bring the quality of this league up really fast.I remember a few years ago when this league was one of the worse to watch with goals scored in an amateur way and no real competition was in this league as a few teams kept dominating it.I know that now with the coming of Ronaldo and Benzema the level of quality of this league has improved considerably but I hope more other players come here to improve it even further.
The Saudi league is mostly improving because of spending too much for the top players the buy from Europa but I think the best they can do is to first invest to grow the young telants from these countries and hire better coaches to teach them a better style of the game which can help them grow much more.
I think that what they are doing now is part of the long process and it's not just because they are acquiring top players from the other leagues to make their team stronger but part of that is to teach and lead the younger players to become a much better athlete in the upcoming years and will make their own name just like everyone else who is successful in their sport because these players that has been acquired from Europian League has more experience and definitely can teach a thing or two. Plus, the investments of coach who have a different approach and experience will too help the whole team to be more impressive and dangerous.
As you said Martinez still needs one more trophy to complete his career it is the Champions League trophy so we can ignore the rumors of his move. 
