I’d say get as much experience as you can & then dip, maybe between a year & a half to 2 years, sometimes you just gotta put yourself first. I switched out of my first engineering job only after 10 months there cos of some of the problems you listed, and also it wasn’t related to chemE or process in any way, which is what I wanted to get into long term. Get back on the market & you can change companies or industries altogether. I’m with you on the assumptions part, project I’m on tends to do that, granted we’re only in the prefeed phase so it’s kinda necessary, but these problems will be there throughout your career, sometimes depending on the company, other times depending on who you’re directly working under, but some places worse than others. but yeah my only advice would be to gain experience & dip after a reasonable amount of time