>* I'm calling FUD; I need proof that different types of employees have different retirement account needs
Not employees. People. Your mistake may be framing everything from the lense of a w2 wage earner. The 401 was created for that person. Since some people do not have access to a 401 or are ineligible there is the IRA- generally those people are low income, if you're self employed then you may have decent income but don't want to deal with the administrative and regulatory costs of a 401 so there's the Sep. If you own a 15 person business and want a retirement plan but again don't want to deal with the administration of a 401 there's the simple. Each of these people have different needs. This is why there are different plans.
>* you said I just want taxes to be lower; that's not the case, and I'd be okay with higher rates; I want programs to be simpler to improve adoption
No, you said you want HSA limits to be higher and allow for premium payment and you said you want early withdrawal penalties eliminated. Both of those are effectively just asking for a tax cut. The former would make things more complicated so your excuse doesn't work at all.
>* 401k and other employer programs lock users in with high expenses for smaller employers; having a program like an IRA travel with you will reduce retirement complexity (who needs 6 401ks?)
This is literally why alternative plans exist. I already explained that above.
>* read nudge and The Paradox of Choice ; when people are faced with too many choices, many just refuse to choose, which is worse than making a mediocre choice; I have co-workers who leave money on the table because they don't want to do paperwork and choose a fund
I've read lots of thaler. I work in this industry. I'm very familiar with behavioral issues which is why I'm certain your idea is bad for the average person. Company administered 401s with automatic enrollment have significantly higher adoption and savings rates than individually administered plans.
If you're interested in similar ideas that improve the world while still maximizing personal choice, I recommend the book, Nudge: Improving Decisions About Health, Wealth, and Happiness, by Richard Thaler .
Ok, here it is:
I hope that's concise enough.