What external synths are you using? Are they Eurorack compatible or just your "normal" hardware synths?
You expressed interest in "straight forward" sound. But the modules that you have are sample-playback, a wavetable oscillator, and an additive source (even though analog). To me, a straight-forward synth sound would include two traditional VCO units somewhere in the mix. But that's my interpretation of that definition. You might want to clarify that.
What seems to be missing are the usual suspects: VCAs, noise sources, attenuators/attenuverters, and mixers of all varieties. Basically all of the boring stuff that makes the difference in modular that most people forget and start stacking up the cool/sexy modules in their rack.
Also, if you're only going to have one filter, I would pick something that can do more than just low-pass.
You have a lot of big modules in a relatively small rack and nothing that really "glues" them all together (boring modules). You might want to start all over and think about modulation first and then sound sources next. The brilliance of Eurorack is the modulation.