Fit shouldn't have stopped the Kings from drafting Doncic. I was among those who valued Bagley just a bit more in that draft, and part of my argument was that the Kings' already had a lead ball handler in Fox, and Bogdanovic brought some of the playmaking you would also get from Doncic. Bagley seemed like the better fit overall, though I did like Luka quite a bit, too. I just didn't see him as a surefire star. Ultimately, I was wrong. Soooooo wrong. Wrong about Luka's trajectory, but also wrong about how to construct a successful roster in the modern NBA. And then the Kings went and drafted a heady secondary creator last off-season, anyway. Haliburton very quickly turned out to be a perfect backcourt partner for Fox. So I've taken my lumps and learned my lessons. You can never have too many creators in today's league.
You also can never have too much shooting. Unfortunately, Simmons does not help in that realm at all. He can't/won't shoot. It's an obvious problem. But Hali shoots daggers from deep, so an initial "core" of Fox/Simmons/Haliburton isn't totally sunk. They'd also represent one of the speediest, deadliest, and most dynamic fast breaks in the entire league, so the team's offensive efficiency would be helped by lots of easy money at the rim (provided Walton loosened up and let them run). And between Simmons' and Hali's collective basketball IQ, the Kings would finally have the kind of smart players that fans have been clamoring for across the last decade. If they managed to hold onto Harrison Barnes, so much the better.
I don't know who the fifth needs to be, but Fox/Hali/Simmons/Barnes is versatile as f***. The defense certainly improves with Simmons in the lineup, and yes, maybe there's not quite enough shooting (unless Fox takes a leap in that area), and maybe the paint is a little crowded at times, and if Philly's problems become Sacramento's problems as a result, well, I'd say there are worse problems to have than making the playoffs year in and year out. And I think that's the kind of potential we're talking about here. With the right head coach who could harness the creativity of a young, dynamic, and unselfish core of Fox/Hali/Simmons, it's not unthinkable that they'd be competing deep into the playoffs eventually.
Now, if the Kings didn't pursue Simmons or were unable to trade for him, there are a few players I really like at the 9-spot this year. Jalen Johnson is my first choice among players that could be available when the Kings pick. I think he provides much of what modern NBA teams need on the wing. But does he project to be better than Ben Simmons? Not really. He's got the same questions surrounding him about whether he can become a serviceable shooter in the NBA. He could be an eventual star, of course, but if scouts thought he definitely had Simmons-like potential, he'd be projected to go higher than the Kings are picking, anyway. So if the Kings are able to pursue Simmons and land him for a package that doesn't cost them Fox or Haliburton, I don't see how they could pass it up, even if Simmons' fit with Fox isn't ideal.
That said, it is absolutely a risk. It could very well crash and burn. In such a case, losing those first rounders would sting. But a franchise like this one needs to swing at opportunities to acquire all-star talent via trade, especially an all-star talent just entering his prime, and especially if it only costs them Hield and Bagley (two players that most of the fan base is ready to move on from, anyway) plus a mid-lotto pick this year and future first rounders that would presumably be in some deeper range of the draft.