I have had two parakeets. One lived for 7 years and one is still alive now. Ami ready for a cockatiel?
Cockatiels are the natural next step they are very similar but if hand tamed and friendly it will require a bit more attention . A conure is a greater commitment as they will demand more interaction daily they are very social birds and may put up a fuss if they don't get enough attention plus they live much longer.
Cockatiels CAN leave in the same cage as parakeets. Just be sure that there are at least two parakeets with the cockatiel. And rearrange the cage before introducing/reintroducing all the birds to teh cage so that they all start on even ground to reduce territory issues .
If you know how to care for your parakeets then you are ready for a cockatiel. Be sure to do some reading about the birds requirements first.
Cockatiels like parakeets are good beginners parrots.
Enjoy.
PS: A cockatiel should not to sharing a cage with a parakeet.
Definately cockatiel conures need a lot of attention and can be somewhat aggressive
