Targeting Trouble

Ok, so one of the issues I am having is changing targets quickly during Heroics and Raids. I was in Magister's Terrace today to get my heroic key, and I spent more time standing around then DPSing. This was mostly due to targeting and then attacking issues. Here is how things have been going:

1) Tank marks skull
2) I right click skull, ready to attack when I get in range
3) Tank pulls, builds some aggro
4) I walk up to mob and start my DPS cycle
5) Mob dies, tank changes targets

Here is where it gets tricky for me.

I can do a few things at this point.

a) Left-click target the next mob, hit an instant
Upside: I will not loot in the middle of combat by left-clicking
Downside: If the mobs are closely grouped, I may end up clicking the wrong mob. Also if my abilities are on cooldown, I won't start attacking immediately

b) Right-click target the next mob
Upside: I will immediately start attacking the next mob
Downside: Again, I might get the wrong mob in a close grouping. I run the risk of looting in combat

c) Click the tank's frame, hit assist
Upside: I will be targeting whatever the tank is targeting, I should start attacking
Downside: Very slow since I have to click a frame and push a button. Usually my mouse is hovering over the Healbot frame for some instant FoLs and Cleanses. That means I have to go to the other side of the screen with my mouse and then hit assist. Also, I have noticed that I don't always start attacking when I assist

d) Click the tank's target, hit an instant
Upside: I will be targeting what ever the tank is targeting
Downside: Once again, very slow. Also I run into the issue of my abilities being on cooldown

e) Make a macro to target the tanks target and start attacking
Upside: Macro will do exactly what I tell it to do, providing consistant results
Downside: Macro will do exactly what I tell it to do, provided I tell it to do the right thing

Option e) seems like the best choice. All I would need to do is unbind my assist key and use Dominos to rebind it to a macro placed on the actionbar. The question is, what is the best way to approach this, and what would the macro look like? Lets look at another set of options, this time for the macros:

a) Set tank as focus, have macro target focus's target and attack
Upside: One button to press and I am locked on to the next target and swinging
Downside: I would have to remember to set the focus before each run, not a big deal, takes two clicks

b) Have macro target the tank's target and attack
Upside: Same as above
Downside: I have to remember to change the tank's name on the macro before each run. This would be big deal as it would be a pain to do it on the fly since I have to change the actual macro in the settings menu

I can't think of any other way to do this then those two options. The obvious choice to me would be option a). Now you might be wondering why I chose to use attack instead of assist. Mainly its because I don't trust assist. I have attack on assist enabled in my options. However, it seems like when I use assist, sometimes I don't even go into the ready position and I just stand there looking around. That is not confidence inspiring to me or my party. By using attack I know I will attack that target. My only concern is if I hit it twice and the tank is still on the same target, will it cancel the attack? That I will have to find out, but for now it's what I will be using.

So this is the macro that I came up with off the top of my head:

#showtooltip Attack
/Attack [target=focustarget]

As far as I know, that should work. The first part should allow the button to flash if I am attacking. This is just so I know its working. You can leave that out if you have more confidence in these things working properly then I do. The second part is self explanatory. Again, this is off the top of my head and may need to be revised later.

Hopefully, this will solve my targeting issues and make the world a safer place for the poor souls who group with me. I may even see a DPS increase..... scary.