TL;DR:
(1) Congratulations cngsoft for this extraordinary work!
(2) I can offer contribution in convenience feature (telling from command line to run something, and exit when CPC resets).
I tested the emulator on Ubuntu 20.04 (actually Xubuntu). It compiles easily, runs smoothly with low CPU consumption.

CPCEC is on a good way to replace caprice32 as my test-run emulator and debug emulator.
I usually test-run my prods with caprice32.Pros: caprice32 is open-source with public history, lightweight, easy to build, has menus,
can be instructed from command line to run some command and exit on next CPC reset since I contributed some code to that effect (
Scriptable wait point command-line option CAP32_WAITBREAK · Issue #110 · ColinPitrat/caprice32).
Cons: imperfect fullscreen handling, ageing dependency (SDL 1), emulation probably imperfect (yet sufficient so far for my needs).
I usually debug with arnoldemu.Pros: arnoldemu is open-source, has some powerful debugging facilities (several windows, context menu, loading external symbols).
Cons: has become difficult to build (dependency on old wxwidget) and has some annoyances, like consuming 100% CPU whenever the debugger is active, no code history and no release visible since May 13, 2017.
(Most other emulators do not fit because they are not open-source, heavyweight or only work on Windows.
https://floooh.github.io/tiny8bit/ is interesting: extremely accurate, easy yet heavyweight build, can run in web pages like
https://gourichon.org/cpcitor/bydate/2020/2020-05-03/ .)
CPCEC may replace bothPros: like caprice32 CPCEC is open-source
with public history (I created a git history from your zips to share on github, with proper commit messages and fixing some issues like corrupted rom in one commit), lightweight, easy to build, has menus.
Cons: imperfect fullscreen handling, can not yet be instructed from command line to run some command and exit on next CPC reset. I can contribute as I did for caprice32. Also, debugging is not as luxurious as in arnoldemu. Interestingly, tiny8bit allows to use any window resolution for status and debugging, could provide inspiration.
All in all, congrats for cpcec!