I like Pilkington's for rust blue myself. I put on light coat after ridding a foam applicator brush of the excess fluid, leave it to hang in my garage and boil 10 hours or so later. Two coats a day this way and done in about a week. I use it full strength and find it to be not overly strong.
I have fiddled with making my own rust blue solution but have not found one I like as much as Pilkington's. I do make my own browning solution from a recipe in Angier's which I modified. The Angier's solution I use gets cut at least 50% to start and then reduced even more as I progress on my brown finish.
I have never really messed with post blue polish or buffing but it would be interesting.
