Embiid is incredible talent as well. 76ers were right to wait those two years for him. Now they only need to draft a proper point guard in the Summer. They'll have plenty of to choose from: Lonzo Ball, Marquelle Fultz look the best prospects but there's also Ntikilina from France, Dennis Smith, De'Aaron Fox - all are top 10 prospects. No better time to be looking for a point guard with your pick. They'll likely also have second lottery pick from Lakers as it's only top 3 protected and Lakers don't look that terrible to defend it this year again. They could likely have a completely new backcourt to pair with Embiid and Simmons for years, exciting times ahead!
I think Gasol's average rebounding, especially lack of offensive rebounds, are a bit of a drawback. He's only getting 6.1 RPG and only 0.8 ORB. Cousins is getting 10.0 RPG with 2.1 ORB, Towns is getting 11.9 RPG with 3.5 ORB (8th in the league only behind absolute rebounding machines: Howard, Drummond, Whiteside, Gobert, Thompson, Noah, Robin Lopez - none of them have anywhere near Towns' overall game). Even Embiid has 7.6 RPG with 2.0 ORB.
It's a bit of a shame 76ers did not get a first overall pick in 2015 draft, they would have almost certainly selected Towns with it and a duo of Embiid and Towns (both would IMO work fine as power forwards, especially Towns who is incredibly athletic) would absolutely tear the league apart (unless they'd have used that pick on Russell which was also a possibility - still much better than Okafor).