Retirement tax questions

So it seems making a non-deductible contribution is quite a bad deal compared to making a roth contribution, looks like the formulas only allow you 50% of the tax benefit if a Roth were made instead. would there be any benefit to just convert the entire Traditional IRA early before the traditional IRA becomes more valuable? or wait until later when taxes are low? or do so during a stock market crash? Is there any rationale that IRS used in developing the formulas that you are aware of as I am trying to understand intent. I only noticed I had a non-deductible in last years taxes when I saw I wasn't getting any benefit for traditional contribution this year, so recharacterized to a Roth, and checked last years and saw I wasn't getting a benefit. I used to see it easier by inspection on the 1040, but I missed it on schedule 1 last year. Thanks!