It's really cool of you to share expertise with another indie dev!
I agree that the wallpapers should all come in one tier. I personally think the tiers before the game should be:
- Thank you/updates/name in credits
- Wallpapers (+ previous tier)
- Full-priced copy of TRoS (no perks, but have the option to "add" a copy of the game to any other tier by pledging the combined cost of the two tiers, instead of automatically including a copy with all of the higher tiers)
- Thorns of War Early Bird
- Thorns of War
And the highest tiers could definitely be more expensive than they are now, especially Lady's Maid. I've seen custom OC character insert tiers go for $900 before, without the promise of writing them into the game beyond a short appearance.
IIRC, she's avoiding an artbook/soundtrack because they aren't an option. I think a lot of the soundtrack is free to use.