Also if you're using a mouse that has web navigation buttons (navforward, navback) those and middleclick also count as bindable buttons, so you have some mouse buttons available even if you don't have a fifty button gaming mouse.
Also also remember that modifier keys can be combined for additional chords. If you have neutral keys, alt keys, and shift keys, you can also have altshift keys. You will probably find an altshift chord awkward for keyboard buttons if you're only playing with one hand on the keyboard (e.g., thumb on alt, pinky on shift, middle finger on 3) but remember you can also chord with the mouse (e.g., left thumb alt, left pinky shift, right hand navforward click) and these keyboard+mouse chords may feel more natural. With navforward, navback, middleclick, alt, and shift, you have twelve more keybinds for actions (navforward, alt+navforward, shift+navforward, altshift+navforward, navback, alt+navback, etc).
Personally I like to put most heals on those twelve mouse chords because I mouseover my heals anyway, so basically I'm just using different kinds of clicks on party members in the list if I need to heal them. I save the keyboard keys for other things like attacks and self buffs that don't need a mouseover target.
Here the buttons to the left are neutral 1-6 and alt1-alt5 (avoid chording with 6; it's an awkward stretch unless you have XXXXL hands). The Rapture and Solace buttons in the altshift row are not for pressing; they're just a visual indicator so I can see if those actions are available. The 4x3 cluster to the right is mouse healing, with <mo> macros for single target actions and gtoff macros for ground placement (
/ac Asylum gtoff places the bubble where your mouse is on the first click without waiting for a second click and without centering it on your target; this is useful when you want to place it under a very large boss but not center it on the boss because people are more to one side). The Sprint and Surecast buttons I can't really help you with; those are bound to my mouse thumb buttons, which you may or may not have. You should put those somewhere easy to reach in a panic since they're time critical buttons.