Normally I would use HEC-HMS, but I needed HEC-1 on this one. There are some functions in HEC-1 that aren't supported in HEC-HMS which the flood control district here uses. They also have a lot of custom software built around HEC-1 that my model needs to work with.
I did find a Graphical Editor "Graphcial HEC1" from Bentley, but it doesn't work very well - wouldn't import certain cards. I ended up buying RMSHEC2000 which is working out pretty well, but not quite as "Graphical" as I was hopping.
Thanks for your thoughts though.