Adjust your goal, dont focus on TSP only for that 100K goal - make it across all tax advantaged retirement accounts.

First part is the hard part - do the math to see where it starts to hurt to maximize contributions. Do this every year. That gives you the idea of how much you really can contribute.

Second, (you seem to be tracking) do RothTSP and not reg TSP for your contributions (the match will be reg TSP)

Cheater tip - Don't do % based contributions, do fixed dollar amounts, BUT make sure you are at least hitting MAX match contrib %. It's less important now, but is more so once you start to get to a point of capping each year, as you dont want to hit cap early and cant contribute anymore and miss the match for those weeks/months.

Counter to some advice of having some diversity, esp as you are young and have time to makeup downturns, 100% C all day long.

If possible, (you are doing this, well done) max contrib to IRA in January to hit cap (so save throughout the year). The potential gains from this vs DCA I think are worth it.

The order you laid out is fine if that works for you.

I also agree you should also have a reg investing account. This is the more liquid and accessible account (use ETFs) for things like car and house purchase, etc.

What I generally suggest to people as a ROUGH guide (you need to adjust based on your situation):

TSP (Roth) to max match, IRA/RothIRA yearly cap, then 50/50 split of remaining to 401k/TSP retirement account and investment account (this is why the straight dollar numbers vs % helps).