ok so here is a guide to Mouseover healing with just your mouse and no keyboard clicking numbers. Works Best with a mouse that has 5+ buttons.
First make the Macros you want for your spells.
/action cure <mo>
/micon 'Cure II"
/action "Cure II" <mo>
Lets drop them newly or already made macros in to any hotbar in HotBar2 and higher.
You can hide the hotbar if you want to clear room on your screen. After you place the macros on the bars you want to use.
We not going to use Hotbar1 for healing unless you want too.
Next lets go to Keybinds. Lets KeyBind Mouse button 5 to hotbar2 slot 1
Now you can just mouseover any target or frame and heal them using just your mouse buttons.
I don't know how many buttons FFXIV supports. I only have a 5 button razer mouse. So if you have 15+ buttons and they all work great for you. If not just use Ctrl and shift with mouse button 5 and 4.
I also moved my party frame window close to my action bars. So I can have it closer to the middle of my screen to click on them as well as other targets.
This has been working great for me. Its almost like having a addon but its not.