I'm just starting to get into this game. I haven't done any deck-building yet, but it will be pretty tempting to play Eowyn every time.
She seems to be the best for actually accumulating progress tokens.
I've only played two games so far. The first one was two-player; I used the Spirit deck and my brother used the Tactics deck. With Eowyn and her special ability, we ended up usually pretty low on cards, but absolutely crushed the first scenario.
This morning I tried that scenario again solo with the Leadership deck and this time I was just creamed. I'm looking forward to tinkering with the decks and trying various things out, but Eowyn sure seems like the top choice for getting those Progress tokens.
I'm totally down with that character having a high Willpower, but with a base value that is at least double that of (almost) every other Hero seems a bit excessive.