Its generally a terrible idea to put the filter/water separator and regulator at the tank unless you at least have an after cooler. You want it as close to the point of use as possible. The reason is that once that compressor runs for a while, air coming out of the tank is going to be over 100F and condensate is going to go straight through the filter/water separator. Plus, all that black iron is going to have rust and scale in it, and you don't really want your tool to have it.
I can't remember all that you have done, I remember you have that bigger 2545 and the smaller 234. Was there a third tank? Will the 234 be used much? I would plumb the two tanks in series and put the regulators at point of use.
What I do, is take my 2 5HP compressors, which do not have after coolers, and run them about 25 feet into a 3rd tank, and from there, I have an outlet that feeds the points of use where the filter/regulators are. I drop about 15 degrees going between the compressors and the 3rd tank, and what comes out of air tank is generally about room temperature, even after the compressors are running for 40-50 minutes straight. Before I had the 3rd tank in series, it was just in parallel, and I would get condensate at my tools. Shuffling some of the lines around and putting it in series all but eliminated it. In your case I would use the 234 tank as an extra expansion device/water drop and then go to the distribution system.