I'm also having the 2 issues you mentioned. The matches are extremely difficult and it's been 3 seasons that I haven't been able to go up to the diamond (to increase the level of the season chests), in addition the rewards are coming very weak.
About the SPS all we have left is to speculate because it could really be a horrible decision for the game or be a watershed, it all depends on how it is implemented, intensity and etc.