Good plan. Sounds like you've done your homework.
Last year, I checked with our plan administrator to make sure I would get the full match if I made the full $18k in contributions early in the year. He assured me that yes, I would.
Lo and behold, the matching contributions were small and stopped completely when I stopped contributing. I reached out again to the plan administrator and received a clarification. I will eventually get the full match, but the vast majority will come in a true-up (due in the next few weeks). The snafu worked in my favor since the markets are lower now, but that's just dumb luck. This year, I am spacing my contributions out to get the full match in the same calendar year.
I did frontload my 457(b) this year (no match).