After much experimenting, I was getting good results with Eco-Flo dyes but I recently switch to Fiebing dyes, mainly because the alcohol-based dyes seem to penetrate the leather better, rather than laying on top of the leather, like the water-based dyes seem to do. Now I have to deal with other issues.
I still haven't worked out the issue of the dyes seeming to be so dark (especially after oiling). Even the light brown turns very dark. So dark in fact, that antiquing doesn't bring out much detail but besides that, my biggest issue is the unevenness that occurs.
Where the leather has been worked, the dye isn't penetrating the leather as well. What I ended up with is a photo negative affect. The leather is dark where it hasn't been worked and lighter where it has been worked. The depressed areas (where the antiquing should be catching) end up several shades lighter than unworked areas areas).
Applying a block, before the dye seems to help but I'm concerned the dye won't be penetrating the leather.
Anyway, I'm open to suggestions.