The Harrier does have some, but it's not in the same league as the A10C.
That "might" change, but I'd be surprised if it's a dramatic update. IIRC, there was talk about potentially adding radar (maybe even air to ground), and expanding some of the weaponry options. The module is also not yet complete. That will almost certainly increase complexity.
If anything, the A10C is the best comparison to the Harrier, as both are basically close support aircraft. Key differences being:
- The Harrier can be used nearly anywhere. In game, that includes from a carrier or FARP, which clearly adds a new dimension to play. For one thing, you might want to learn carrier operations. Landing one at night onto a small carrier is quite a challenge
- The Harrier is much faster, but also burns fuel much quicker.
- The Harrier is a more capable aircraft in an A2A duel. Don't get me wrong, you shouldn't chose to get into A2A unless you need to. Right now you have no radar to find an enemy and only heat seeking missiles. It's also not got the energy capability of fighters in game. All the same, it's still better than the A10
- Similar weapon load options, although you can't carry as much on the Harrier. The only real difference being the lack of the GAU cannon, whilst it brings in the Sidearm anti-radar missile (which is "ok"). Again, that might change with additional new weapons for the Harrier.
The key thing is that the Harrier is unique in it's flight capabilities. If that interests you, then it's a good aircraft.