We're playing 5e, too. I like it, but agree that it's far too basic at times and complex at others.
Characters don't have nearly enough options available in some ways. A typical character has fewer than five skillsmand they rarely go up by an appreciable amount. Learning something new is especially difficult. Magic users uses are either stuck knowing very few spells or forced to only use a few different ones per day.
This rigidity forces other complexities. There are way too many playable races leading to wacky parties. Our current party is goblins, some sort of weird goblinlike creature, two robots, a dwarf, a variant human, and a vanilla human. Every single one of us is a different character class ranging from fighter to artificer.