Shield Lob is excellent as an "inbetween" move for when you are closing on a target or leading a target back to a certain spot, otherwise a full comboed RoH is by far going to be the largest emnity generator in your arsenal. Yes there is lead-in time to get to a full combo RoH, but as others have suggested if you can prep it before hand and be ready for the spawn, then all should be gravy.

Quote Originally Posted by MithrasInvictus View Post
Start with a shield lob on your way to the mob that you want to catch, by the time that you get there, your cooldowns will be ready. Throw a flash at it, then drop circle of scorn, then flash again, then spirits within, then commence your Halone combo (This is gross overkill for most scenarios, but it's the fastest way to stack your enmity). If you need to recover it from somebody that took it too quickly, use provoke on it to give yourself top-tier hate, then shield lob it to secure your pole position on the enmity gauge and proceed as you normally would.
Your suggestion may work for trash packs, although I would personally start my RoH combo and fit in CoS and Spirits between the combo attacks. However that isn't how you should approach establishing aggro in this instance, Chirada in Garuda EX, or in most boss fights or single target fights.