Would you rather sit around and do nothing between Raids? Or do the daily SM Op/HM FP for comms that aren't really needed if you've been at this for a while? Or how about rolling another alt? Frankly, it's something to do -- much like the wealth of grinds in other games, that were purely for titles or a chance at rare drops. At least this one offers special items and equipment, in addition to titles and "prestige".
"As your Reputation Rank increases, new rewards will become available to you. Throughout the galaxy, you will find Reputation Vendors associated with each organization. Special rewards with Reputation Rank requirements can be purchased from these vendors. Items and equipment with a Reputation Rank requirement can only be purchased, used, or equipped if you meet or exceed the rank requirement."
(Incentive beyond a title)
The "old" content are heroics on Voss (not the entire questline..), Section X, and Hard Mode space missions (presuming many people do the latter). Additionally we'll have the Gree enclave events.
In my opinion, something is better than nothing. I'd rather have things to do on my main, and encourage Bioware to do more while offering constructive feedback, as opposed to complaining about what progress they do make. Complaints rarely motivate one to work harder, especially when the community is impossible to please. They're damned if they do, damned if they don't.
I have to admit i would rather sit around fleet waiting for WZ or FP pop than do dailies and maybe even this new grind. I did dailies once where i did them all and have never done em since and i will never do them again its boring.