Hi -
This should be an easy one for the audience as I am still a beginner..
Situation: I have purchased bitcoins on Coinbase and left them there on what they call wallet.
It really frustrates me that Coinbase does this. Technically they have NOT provided you with a "Bitcoin Wallet". They have provided you with a Bitcoin based "account" on their service. They've just chosen to use the word "wallet" to describe their accounts. This tends to cause confusion, as an actual bitcoin wallet provides the wallet owner with control over their private keys.
Question: does it make sense to transfer the bitcoins out of Coinbase (they are not a large sum)
That depends on how you feel about the current situation.
Right now you do NOT have ANY bitcoins at all. What you have is a promise from a company called Coinbase that they will send a specific amount of THEIR bitcoins wherever you ask them to whenever you ask them to. It is up to you to decide how much you trust them to be willing and able to deliver on that promise.
If you transfer the bitcoins to a desktop wallet, you will actually have bitcoins of your own, completely under your own control. This of course means that you are completely responsible for maintaining the security of that desktop wallet. You are responsible for the loss if your computer crashes and you lose your backup. You are responsible if you get malware on your computer that steals your bitcoins.
am I exposing them to any theft risk by transferring them to a desktop wallet first and to a hardware wallet afterwards?
If you fail to secure your desktop wallet properly, and a hacker or malware gains access to the wallet, they will be able to steal your bitcoins.
