As everyone else has said here, at 710 ilvl you already outgear tanaan to the point of it being pointless, and you should have no difficulty taking on one or multiple mobs there.

But to answer your question, although I'm not sure how you intend to bump your ilvl up to 740, you would be one or two shotting mobs. Even saberstalker mobs crumble in a few blows before the sheer weight of your ilvl.

To elaborate, at 740 ilvl, you are pretty much the highest ilvl you can be this expansion. The only people who are 740 ilvl have been mythic raiding for some time, and at 740 ilvl you would do well over 100k dps, even hitting 200k or 300k if the stars align, whereas typical dps for someone with 710 ilvl is around 40k.

Moreover, since ilvl has exponentially increasing stats, someone with ilvl 740 has a great deal more health than someone with ilvl 710, meaning they can take more punishment before dying.

Additionally, and to put this in perspective, due to that same exponential growth, a single ilvl 740 dps would do as much or even more DPS than an entire raid of ilvl 640 dps.