I may have spoken too soon about beam weapons. I still favor them, but the latest enemies I've come up against seem nearly immune to them. I've seen the Valkyrie animation a lot lately.
A tip: Shoot the floating fat undead guys. They come with an army of nigh-invincible undead soldiers. Once you dispatch the leader, most of the soldiers seem to disappear, and you can kill those left much easier. I think the floating fat guy keeps them alive.
I found it difficult to target the floaters from within their army, but distance makes it much easier. Distance also makes it easier to kill them as guns have a longer range than the floaters' area attack.
I have finished the game. I had a very difficult time trying to take down Hel. I think the problem consisted of me dying so often that my weapons and armor all had zero state. In that condition I could not inflict any damage on Hell. The next time I played I repaired everything and re-spec'ed my skill tree. After that I successfully got to the final battle with weapons and armor in non-zero state. Then she went down in pretty short order.
I have one complaint about the game, something that all the reviewers seemed to miss: The game (with tutorials on) does not adequately educate the player in how things work, especially charms and battlecries and the skill tree. That information may reside in the manual (I haven't read it yet), but players should have it all available to them in-game.