1) You're a brand new team so the first season will be tough, especially if you've never played this game before and/or if you are new to basketball
2) You only have 1 player older than 23-years old and he's 27. He's a shooting guard with potential to be a perennial all-star. Considering his age, he likely won't ever dominate your league but he's good enough to get your team started.
3) You have two potential perennial all-star point guards, one of which you are selling. I personally think you lowballed the starting point for the sale but that's just me. A player that is as young as he is with his stats and his potential should go for higher. Typical rule of thumb is that if you're going to sell him anyways, start high and continue on that path because eventually someone will buy him. You've still got until the 15th for him to be bought for more than he's listed though so maybe you'll luck out.
4) Your star players seem to be focused around your guards with the supporting cast being the interior post players (Center/Power Forwards). I don't know what stats your players have but I'd probably focus more on the outside game until you can find interior defenders. On my team, I started out with an excellent shooting guard and a solid supporting cast around. Ran the Run-N-Gun offense and he we won games because of him. Over the years I've built the offense around him starting with the SF and PG and letting my solid-but-not-great interior post players play until I found the perfect interior players for my team. Now I've got outstanding perimeter defenders and shooters and have two interior post players with focus on rebounding and defending the inside shot and I have a very solid inside defender coming off the bench. I utilize my players strengths the best I can by knowing what they offer when I see them in action.
5) You've got a solid team so you should need to sell out your players in hopes of starting fresh. You've got fresh young talent, just need to learn to utilize what you've been given to start with. You'll need to go into next season with the mindset that you're finding out your team's strengths and build around those players. You've got to have a solid foundation before you can put the walls up.