94 owner from new. I see OBD1 and no airbags as a plus. VAF vs MAF an issue to consider. Exhaust tougher to source versus 95 plus.
OBD2 does make diagnostics easier. The OBD1 blink codes can be pretty unhelpful, and the ECU *will pull timing, limiting power, if something isn't right.
When i bought my '94 11 years ago it had a check engine light that the PO's mechanic "couldn't figure out". I forget the exact codes, it was something about too rich and too lean? Reading between the lines in the FSM, all the ECU was blinking at me was that it was idling rough. I knew it was idling rough because I'd been driving it.
It was real lazy on a freeway on-ramp and struggled to reach and maintain 65mph.
Replaced both O2 sensors as well as some of the O2 sensor wiring, replaced like 16 feet of vacuum lines, cleaned and wiggled many connectors, and put band clamps on the air duct and THAT problem went away. And then i had to replace the rear knock sensor which was super fun too. But since then it has been solid. Passes the exhaust sniffer test every year, good acceleration, can cruise at 80 all day long.
Granted, early OBD2 isn't as in-depth as modern diagnostics.
The OBD2 engines are a little more efficient and it is certainly easier to turbocharge them. The VAF on the OBD1 trucks has a limited range for obvious reasons.