Final Fantasy XIV Gil, FFXIV Gil

Skills: Staff Mastery - (you only use a staff for the M.Atk, to boost your heals, and Staff Mastery only boosts the Final Fantasy XIV Gold P.Atk mildly... thus, it's worthless. Don't waste your JPs)

Mace Mastery - You can put 3-4 points into this to get you through levels 1-25 if you like. After that, you'll never use a mace again (if you're a good healer). If you want to solo later on, put more points into it then.

So, do quests till you're level 25 or so. Focus on raising your heals as much as possible, along with Wizardry Mind and Mental Amplify.

As far as equipment goes...

Weapons: You can buy an r2 mace when you reach level 20 if you like, but you could just get by with your r1 mace for a few levels also. You won't need a mace after lvl25, so the only important thing is to have an r2 staff ready.

When you go into a dungeon, don't take your mace - you should never, ever be using it. As far as using strike cubes... it's not a bad idea, but it's not a priority. It's more important how you heal and that you sit often use deluxe spell potions, etc, than how much you heal for.