It depends.
If you have apps that store data locally (on your iPad), then yes, you would run the risk of losing data if you performed a factory reset of your iPad since your iPad would be erased and with it all the data that was locally stored on it.
If you have apps that store data in the cloud, then no, you would not lose data if you performed a factory reset because if you re-installed the app and logged into the account for that app your data would be restored since it is stored in the cloud and not your iPad.
Chances are most of your apps store data in the cloud but you could have some apps that store data locally. There is not an easy way to know which is which.
Performing a factory reset of your iPad will not affect any data that is stored in the cloud and therefore it will not affect any of the data that your iPhone has on it (assuming your data is seeing data that is stored in the cloud.)