I'm reminded about something. It was only the in the last three years of the pro lab's existence that Ilfochrome prints were offered from digital files, and the results were never good. They actively discouraged the use of fill flash in outdoor scenes (chiefly because of how unnatural an appearance it imparted on the image when printed) and eventually dropped off the file-to-chrome print option because of the too-common added expense of working up substandard files in preparation for printing: that is to say those who used flatbed scanners and "had their own way" actually had no idea what they were doing and incurred up to $800 in on-costs before the 'chrome darkroom even had the enlarger turned on!
Ilfochrome was never impossible to do; just two contrast variations and the sheer expense in time and money and skill made it quite the challenge; true, many home users with their own darkroom dabbled in the early Ciba kits, producing prints for Club exhibitions — I was one of them from 1988 to around 1992. I was never, ever a fan of machine-Ilfochrome prints. That is they lazy way to go.
My printer was often quite venomous about the distribution channels, but mostly literally spitting blood over unstable quality control.
And Velvia? Let's not be too harsh with this dear Goldilocks. Velvia remains the gold standard for printing to any process; earlier RA-4 testing from Velvia (and E100VS) was nowhere near as impressive beside Ilfochromes. We tried and tried and tried and twisted every trick there was to up the ante with cheaper processes, but it would not be. As with anything, to get the best, a lot of money had to be spent; a lot of professional (printer) time had to be invested; a lot of experimentation, dialogue, testing and retesting. Then at the end ... it was a marvellous thrill — a blast, to have the finished product delivered to the door ready for spotlights, and I will never offload the last 400 or so frarmed Ilfochromes: they are all true legends of their time.
It all comes down to what you want, what your 'signature' quality mark is. RA-4, if you can do it yourself, will likely produce results you will be pleased with. But if you are producing for exhibition and sale, the prints you create are going to need more than "produced in a darkroom" as their selling tagline. It will always (for as long as it's available) be possible to produce a masterclass B&W print through skill, judgement and labour and it will be comparatively cheaper to do so. But colour, and we see the world in colour; it's the archaic RA-4 or not-so-new-kid-on-the-block, hybrid: that's your two options.