"Mods" are not always better. Truthfully a stock ignition system in top shape is all an engine with stock internals needs. High performance ignition systems exist because modified engines with higher redline and higher cylinder pressures have conditions that make it harder for the plug to fire. Your engine is stock internally so you're not going to see much if any gain using fancy coils or wires that come with zoomy looking stickers
I put high output coils on most of my engines, even the stock ones. But do so because it makes them less prone to flooding when things go wrong or it's ten degrees below zero and the fuel is fussy about igniting. They don't do anything for mileage or power over a properly functioning stock coil. That's the truth.
Multi-spark systems will do something for part throttle power & efficiency but not a lot on a fuel injected engine. They excel with carbureted stuff that has inferior fuel atomization. And you're not going to see much if any gain WOT on a stock engine unless the engine has a mixture problem. The downside of a multi-spark system is they're not as reliable as a stock ignition system. And they're pricey.
Just a few thoughts from somebody that's been there. Others will probably disagree.
PS, the parts on are grand cherokees are chosen for a lot of reasons. Like if they came with dana 60/70 axles we'd all be making 2mpg less, the truck would ride rougher, accelerate slower, and have a higher sticker price. Your bigger is better philosophy just doesn't work when designing vehicles, weight and parasitic loss are the enemy, even if cost is thrown out the window.