Blue resin may not be the best color to start with for a DLP system. It seems that some people with DLP systems have been able to print in MJ G+ blue, but generally red and black are the easiest for beginners.
You also shouldn’t think of the build area as a source of speed. Print things flat when the part needs to be flat, not because you want it to print faster. If you print the part in an upright orientation, that would allow you to adjust the projector to a higher XY resolution setting, reducing exposure time, and reduces surface area, reducing lift distance. Reductions in exposure time and lift distance are the primary means to tune a print for speed, but only once you’ve gotten the part printable.
One the topic of pigment settling and support overcure, it surprises me a bit that you’re experiencing so much support overcure. I do add pigment to my MJ G+ when I use it, but that mainly improves surface finish.
For instance, if you look at this part (which I printed at 93 micron XY resolution with MJ G+ black and no additional pigment):
This part was printed flat against the build plate, but has a bunch of “downward” surfaces that face to the build plate. You can see that the surface finish is impacted by overcure, but not to the extent that the shape of the surface is significantly altered (e.g. blobs, hills), even on the thin bridged part that is parallel to the build plate.
In comparison to the version with pigments added, the surface finish is significantly better (ignore the difference in the roundness of the horizontal edges, there were fillets in the earlier model which I removed for this version, dimensionally, the surfaces are the same):
Also, both prints done in about 105 minutes and I didn’t stir a single time for either. Pigment settling varies a lot based on pigment.
Whatever pigment MJ uses seems to settle quickly. This is true for their pre-pigmented mixes too. Thus, the need for mixing to prevent settling remains even if you don’t add your own pigments. The default G+ black definitely looked settled after the print run.
On the other hand, after adding TAP Plastics pigment, I noticed that after the print, the pigmentation of the remaining resin in the vat was still even with no noticeable settling. I would encourage you not to be afraid of experimenting with pigments, you’ll significantly improve your results and ease of printing.
Now, if you really want to print flat against the build plate, maybe because you have a dimensional part that really needs perfectly flat surfaces (like say, a mold), you can do that. The key here is to lift slowly:
The above part was printed with very slow 10mm/min lifts across the entire part, and also printed on bare silicone (although I think with slow lifts, it would be possible to print this on a stock v2 vat).
In my opinion, you should focus on first mastering printed the part tilted with supports before trying to print flat. You really want to iterate techniques that start from a point where you can make gradual improvement rather than create a number of constraints and try to satisfy all of them at once.
With supports, I would start with exposure and seeing whether or not your exposure may be too high. If the supports are building solid and not breaking, I would leave those settings as is and then try dialing back the exposure for the part starting 1 or 2 layers after the transition from support to part.
Pictures of your prints and the problems you’re having would also be very helpful. For instance, I don’t know how tall your supports are - it may be that if your supports are taking a while to come out, that you might be experiencing pigment settling. The rate of pigment settling is not really related to whether you add your own pigments or not, and more to the type of pigment present in the resin. The default pigment will settle as well.