Micha StitchBuddy is rather nice, but for a professional usage not even as powerful as e.g. PE-Design.
Sorry for that. Please correct me if I'm wrong.
No, you're absolutely right, and I'd like to be transparent and honest about limitations and manage expectations:
StitchBuddy never intended to address the professional market: Its main target group are hobbyists, who want to organize, preview and maybe tweak designs without paying big bucks. Over the years I added some capabilities which might suggest a different purpose, but that's still my ambition, and is also reasoning the rather different price range: PE Design is approx. 1,500 USD, while StitchBuddy costs 50 USD.
Regarding PES file formats: I know that PES v1.0 is rather outdated and comes with a severe size limitation, especially when considering hoop sizes of current embroidery machines. Thanks a lot for the link to PES file specifications, much appreciated. I'm sure you have realized, how often it states "unknown" for certain data - which is a no-go for writing any file format: Every single byte needs to be known to write a consistent file, as without this information the result might be corrupted and even harming a project or a machine.
So, for the time being, saving larger PES designs in a different format (like DST) is still the only bypass, and hopefully acceptable if only a few files are affected - certainly not for a professional user. And at least in StitchBuddy color information can be preserved by using an explicit thread chart…