Without any adjustment, it seems the STh 4 at 21 degree, and the STi2 #5 iron at 25 degree are the best out of the box progression. 5w at 18, STh2 4h at 21 and then the STi2 #5 iron at 25. On paper that looks the best from a loft standpoint. The Hybrid is longer, usually, and you might hit it a little farther than you would a 4 iron of the same loft, so that might give you a little gap between it and the #5 iron, but I don’t know how far you hit your #5 iron. Also, if you have the ability to take a little off the hybrid when needed, then that eliminates that potential issue.
The other option could work as well, even though the loft progression does not seem to progress as well. 5 wood at 18, STh 5H at 24 and DBM 6 iron at 26. The higher lofted hybrid could give you a more normal progression from the 5 iron to the hybrid, but then might leave a little more gap between the 5 wood and the hybrid.
Honestly, you’re probably just going to have to pick one see how the distance progressions work. No way to know for sure without testing.
Britt Lindsey