Season SP

Not sure if this has been mentioned previously but I find the game near pointless to play towards the end of the season.  I have completed the season pass and the game seems way less enjoyable when only playing to achieve rivals rewards and squad battle games.

I am a casual player so do not compete in champs and the tournaments are hit or miss although I did find gauntlet 4 to be the easiest for some reason. 

Is there a way we can stack sp to gain levels in the next season pass or be rewarded for it in a different way?