You're good to go at level 2. Don't rush to buy or sell anyone.
A four star starting lineup will be more than good enough to finish in the top half of the table next season.
But save, save, save! Watch videos for rest packs, your players condition is not good at the time you took the photo and you only have 3 rests avaliable. Watch all the videos you can and save all the packs you can.