OTA updates will work but you will lose root. Better off finding either pre-rooted updated firmware on XDA or install stock firmware using Mobile Odin and there is an option to 'keep root'.
For you newly rooteds my number 1 first thing to do... change the DPI. You'll find you can see soooo much more on the screen. Some Samsung apps don't look very good at lower DPIs but most downloaded apps will look much better. Experiment first with this app
https://play.google.com/store/apps/details?id=lv.n3o.lcddensity, anything you change is undone when you reboot.
If you like the change it's pretty easy to make permanent by other means.
EDIT: Forgot to mention 240dpi is the sweetspot in terms of looks and app compatibility.