I very rarely use the R2 attack, but I'll try it out for various weapons and see if I want to invest the ember on something other than the Broadsword.
Oh oh, by the way, the embers aren't one time use. Once you have the ember, you can scale any weapons up using it, the problem is that you also need the materials (titanite shards, large titanite shards, chunks, slabs) to elevate it to the next level. Basically, the ember is unlocking the ability to scale your weapons to +10.
Also, I would recommend you try and get comfortable with using R2. Dark Souls gives you a lot of weapons with some really varied movesets and knowing the best tool to use in the situation is what makes the game such a blast to fight through.
Light attack | R1
Heavy attack | R2
Leaping attack | Forward + R2
Guard break (dat kick!!!) | Forward + R1
Running attack | Hold B to run, then press R1 while running
Dodging attack | While not moving, tap B to back step, then tap R1 to lunge forward and attack
Then of course, you know that you can press R1 multiple times to do multiple light hits, and if you're feeling ballsy like you don't need your shield, you can press Y to hold with both hands, change your moveset up, and increase your damage output.
Along with that on the left hand you have
Block (or light hit) L1
Parry (or shield bash) L2
With light shields/no shield L2 will parry, and with a heavy shield you'll do a shield bash.
Whenever I got a new weapon, I liked to just run through the basic assortment of moves available above and see how useful they looked and get a feel for it. Once you get a basic competency with what the attack options available to you are, the combat really opens up.
Stuff like parries are tough to learn because missing one is so punishing, and it's not something you need to master, so don't feel like you need that as a priority. But once you do get decent at them, pulling off a parry then obliterating your enemy is an awesome feeling.