Buy European

That’s not a really accurate characterization.

Grippens would be comparable in mission capability, capacity, speed, maneuverability, and range to a late-model F-16.

Their Grippen’s key benefits are (as you said) simplicity and maintenance cost, but also (notably, a divergence from the Viper) robustness - they’re designed to be frontline fighters, and don’t have any problems with taking off from extremely austere airfields (read STOL-capable, can easily use stretches of highways to get in the air).

In terms of BFM: Grippen wins, hands down. Fat Amy is not nearly as maneuverable as modern 4/4.5gen fighters. If a Grippen gets to the merge with an F-35 (which is an admittedly big “if”), the lightning is probably not gonna have a good day.

The F-35’s primary strengths lie in its incredible sensor fusion and connectivity - when the ecosystem is properly hooked up around it, it can lob a missile or JDAM at something by using the sensors from something else - or more importantly, vice versa (F-35 as a sneaky forward observer, F-15 EX missile truck further back with like 16 AMRAAMs strapped to it).

The F-35’s primary weaknesses are cost, complexity, poor mission availability, and nowadays, that the current US regime is probably gonna try to shake you down for it at some point, and also, who knows if there’s a kill switch somewhere in there. The whole integrated system is incredibly complex, and the details are almost entirely classified, so it is honestly not even really possible to do an integrity audit of whether there’s a switch the USAF of whoever to hit that locks weapons, blocks connectivity, turns on radio beacons (kills stealth), and so on.

The last bit there is a hypothesis on my part… but, having worked in defense, and knowing how ripshit the US government was at the fact that the IRIAF was (and still is) running arguably the best US fighter in production for a good long while (to the extend that they imo prematurely killed the whole program when it still had a lot of potential left to explore, simply in the interest of starving Iran for parts - USN F-14s were destroyed on decommissioning, not mothballed like pretty much all other airframes), something like that existing would definitely not shock me.