We used to have a win streak system when battle arena was first introduced but then it was dropped . The league points system was tedious even when boosted and it was much better for rankings based on MMR rather than league points. I mean MMR was still there but at the time when arena was first introduced, you couldn't tell what MMR you were and another thing is that there was only division 1 of every league.
But when league points was removed , apart from matchings based on MMR instead of points gained , you also had a higher chance of getting legend and eternal chests instead of constantly farming epic chests only. Also advert to boost the chances. Since patch 2.1 or so, arena has changed alot from balance but also easier trophies than first introduced.
Stables? That sounds interesting but I don't really understand it. Then again, I haven't experienced games like these.