Lots of recommendations for GURPS / GURPS Dungeon Fantasy and I came to recommend the same.
GURPS gives lots of option to ’regular’ characters in combat. We are about 60 hours into a Dungeon Fantasy campaign and have a party with a swashbuckler, martial artist, knight, wizards and cleric. The swashbuckler probably has the most options in combat due to her high levels of combat skill. Rapid strikes, deceptive strikes, called shots. And that’s after the high level decisions around combining moving and attacking to get into an advantageous position. GURPS generally doesn’t put ’realistic’ options behind a ‘feat lock’ so anyone can try disarms, trips and so on. It just makes skill count so that, to do these things reliably, you need to be highly capable.
The common wisdom in GURPS is that a ‘fighter’ has more strategic options in combat that a ‘wizard’ as GURPS magic spells (using the default magic system - others are available) are smaller and more specific than DnD spells, but wizards typically know more of them and casting is based on fatigue rather than spell slots and there is no memorisation so you have your full repertoire available to you when you need to pick a spell to cast. In GURPS, magic isn’t really about dishing lots of damage, at least it isn’t about dishing out more than a skilled warrior can. Our Wizard can build up to a 4d6 fire blast which is pretty impressive but costs a couple of fatigue points every second it is use, so they can only sustain this for a few attacks. By contrast our knight does 2d6+8 Cutting damage when using his bastard sword two-handed (and that type of damage is multiplied by 1.5 once it gets through armour in most instances). He can keep that up every round, can attempt a wider range of combat manoeuvres due to his higher skill, and is just simply more likely to hit in combat. But: the mage can fly, turn invisible, glue enemies to the spot, lift donkeys up a cliff face (this was important in the last session!) so it all balances out to a greater or lesser extent.
GURPS in general and GURPS DF specifically are a different type of fantasy game than DnD, with different strengths and a different flavour. It could be what you are looking for and whilst there is, of course, a learning curve our experience is that this isn’t huge and the DF box set in particular is well written to take a group new to GURPS through all the details open to you.