I actually take HS a lot more seriously than bridge

I invested no money in it out of some silly principle and now I find it hard to back out even though the game is clearly worth money. My collection is fairly extensive though I'm missing several good legendaries (Tirion/Jaraxus/Malganis/Thalanos/Van Cleef/Cenarius/Grommash are the playable ones), so it's difficult to justify sinking money into it.
I mostly played arena because it looked like there's nothing to gain in ladder. I feel like I'm an infinite arena player (if I need gold I do several arena runs), but ever since I started tracking with Heartharena it stubbornly claims I have a 6.6 win average.
This season I decided to try and take ranekd play a bit more seriously. I laddered up to 7 with a combo druid pretty easily, and I'm now at rank 4 with Strifecro's Grinder Mage which is seriously one of the most fun decks I've played. Rank 4 seems to be the cap though, I catch myself losing for subtle mistakes the opponents are now smart enough to exploit, so I think I need to improve as a player to make it to legend.
What about you?