Barca has to be the favorite going into this season, since all key players return except Xavi. A couple of the key players (Iniesta and Alves) are getting old enough that they might not be able to play at the highest level for an entire season, but they both were fantastic when they were most needed towards the end of last season. Until January, the squad is thin enough that some bunching up of injuries or suspensions (never happened last season) could make the title race more challenging. Barca will be very tough to catch in the second half. 90 to 105 points.
RM has to see if they hang on to Benzema and Ramos, they would be hard to replace. I think this season's new FB will be a lot more successful than the last few they have brought in. RM got unlucky last year with Ramos, Modric and James out during the bad period that cost them La Liga. You've got to wonder how their morale will hold up with so few titles recently and switching to a lower quality manager. I have no idea how this season will go for them. 80 to 100 points.
AM has both key losses and key additions. Getting Vietto is huge, both for his current level and his potential. Might still need to add a top midfielder and a top CB to improve from last year. 85 to 95 points.
Both Valencia and Sevilla looked good enough late last season to be CL final 8 level. Neither will finish ahead of Barca, but maybe one could finish ahead of RM. Either could get up to the 85 point range.