I too am late to the party and congratulate you on your choice. For my input I would only say that perhaps I look at things different;y but it seems to me that what a ward or warden gets their name from could very well be what they guard, but it also can be from what they guard against, which puts me in mind of the FellWarden as one who guards against anything fell, keeping the fell influences out of Dwarven lands. Funny thing about bounders though, I do consider it a Hobbit contrivance myself, however When Ringulf left Erebor and his position as a Scout of Ravenhill, he ended up during the scouring along with all the bounders not under the thumbs of Sharky and his men. For all intents and purposes he was lumped in with the Bounders. He may not have had the cap and feather of a one, but he had the heart of a Bounder!
A heartening sight by Day or Night, Dwarven warriors bold! To add their Might to any Fight, Precious more than Gold! A Dwarven friend is to the end, Never shall they fail! Their word does not bend, wherever they wend,
through Cavern, Hill or Dale!"