In NL (EU) Cinema 30 € 4600 and X6800h € 2500 as we speak. So also still a big difference. Only difference is amplifiers and power supply as the ‘back ends’ (DAC-board, HDMI-board, HEOS-module) are similar. Bought my 6800 over one year ago for around € 1600 in Black Friday sale. Never hit that price again and was for one day only… With F/R/C and surrounds driven by Marantz’ MM 7025 and 7055, also bought during sale or 2nd hand, I’m paying less than a 2nd chance Cinema 30. Now with full Dirac installed (also Black Friday deals) I can say this is still a lot of money but worth every €.
That is very interesting, so in EU countries the price premium for the C30 is huge, yet for the C40/C50, and the so called "dressed up" X4800H/X3800H, the list price premiums are usually around €200 - 250, much more acceptable, even a good deal to some extent. That's based on list prices, dealer discounts will vary and may increase the gaps.
Come to think of it, the Cinema 30 does offer more differences than the case of C40 vs X4800H that are closer to non identical twins:
C30's additional costly items:
- Much better physical layout, more copper shielding better/bigger heatsinks
- Toroidal (this one is more marketing than..), but definitely stronger power transformer.
- Bigger block capacitors.
- Much larger enclosure, to house the larger PS
- Upgraded HDAMs (personally, imo they are a waste but they do justify the increase costs).
- Add dac filter option .
Whether all these explained the €1000 premium vs the €200 for the C40/50 vs X4800H/X3800H, I am not sure but there is something substantial there.
Since you are using external amps, and got a good deal on the X6800H, I think you did great.

As pre/pro/dac, I see no reason for the C30 to be superior unless you are the subjective type and prone to biases of different kinds, or have exceptional hearing that may apreciate one of the two dac filters more.