When Mercenaries was released, I had an alternate F2P account, which I used to spend over 10k gold on testing out the new mode, while giving what I thought was quick and valuable feedback:
“1). The PVE sucks and much could be done to improve dungeon runs to make PVE much more fun. There are so many things that can be done to improve PvE.
2). Mercenaries is way way way too grindy.
3). Pack values are horrible, since they lack duplicate protection and included cosmetics. Mercenaries packs provided the worst pack opening value and experience that I have ever encountered in a game.
4). PVP, like most of Hearthstone, suffered from major balance issues, which doomed PVP to feel very repetitive.
5). A build up of huge surpluses of unusable coins for maxed out mercenaries felt bad.
6). Mercenaries did not seem ready for release, which made it feel like players were duped into paying to alpha-test a new mode.
In summary, rushing a mode that was too rawly designed (and with very greedy marketing strategies) to market without being able implement improvements quickly has doomed Mercenaries into being a niche mode that feels more dead than alive.”
Even players who dump a lot of cash into Mercenaries to reduce a lot of the grinding, so that they can mostly focus on playing PvP competitively, probably still hate the amount of grinding they have to do. And after they spent all that money, they quickly end up playing players, who mostly did the same thing—spending a lot—only to be facing the same 4-6 best comps over and over again. How boring.
Many of the players who play Mercenaries only for the PvE are an enigma to me—there are so many better games out there to play.