Are there any D-50 type patches?
No. I doubt it will happen anytime soon either. But there are the ‘Juno 104’ and ‘Glass FM’ patches. There is a pd dx7 patch but it’s not on the organelle yet. Complex synths are hard to make.
Zone is a wavetable synth patch that blends four different waveforms. This is similar to the wave blending capabilities with the D-50’s joystick. The waveforms are .wav files that can be changed in the patch folder.
Nothing for playing synthesis and tiny samples combined?
With orac you could use a sampler module and a synth module together perhaps?
Using orac could work.
The attack transient samples on the Roland LA synths are copyrighted so you’d need to find or make a set of similar samples.
You could also try combining a synthesizer with a strong attack (like tuneddelay or rhodey or rngs) with a subtractive synth module.