I’m pretty burnt out on tackling Super Gem Fighter / Pocket Fighter right now. I took a little break and did some more research on something quite interesting I had found a while back: English text in Koutetsu Yousai Strahl, a horizontal shooter and a favorite among shmup fans.
EDIT 2018-11-28: As of MAME 0.203, there is a world region dump of Strahl. It contains the English text that was found in the Japanese version, making this article relatively useless. Oh well.