Can you post your actual gear sets? I don't see how you can have 468STR and 432VIT (your i90dps) at the same time, and are you sure you have 448STR and 482VIT in your Gryhphonskins? Are those your numbers WITH party bonus? Please post them raw if you can for a more accurate comparison.
Let me preface the next section by saying subtract 30 from VIT and then add 30 to STR. For some reason the site doesn't let you adjust your point distribution.. or I just haven't figured out how.
Here's my i90 DPS set:
http://ffxiv.ariyala.com/LT4T
STR 469, ACC 473, CHR 413, DET 307, SSPD 372, VIT 416, Parry 410 [Adjusted for +30STR -30VIT difference on build site. No food.]
STR 469, ACC 473, CHR 421, DET 322, SSPD 372, VIT 431, Parry 410 [Adjusted for +30STR -30VIT difference on build site. + HQ Buttons]
Now, here is something close to what I would consider to be close to a hybrid BiS. Balancing stats for maximum tanking/damage effectiveness without using i70 crafted gear:
http://ffxiv.ariyala.com/LT5A
STR 430, ACC 472, CHR 363, DET 302, SSPD 368, VIT 461, Parry 472 [Adjusted for +30STR -30VIT difference on build site. No food.]
This build has multiple advantages. Firstly, with party bonus your STR will be high enough to reach 25% damage parried, AND your parry is at a reasonable number to parry more often compared to the DPS setup. A very good balance IMO. The CHR is a lot lower, but your DET is relatively the same so you can at least rely on your baseline numbers to remain similar. I can do what I need to do with a pretty decent rotation at 372 SSPD on my DPS build so dropping to 368 doesn't hurt. For reference.. the difference between 372 SSPD and 388 SSPD changes my GCD from 2.47s to 2.45s, a marginal difference.
There's also flexibility here with food options so I would suggest either HQ Buttons again, or HQ La Noscean Toast for more Parry. Both options obviously give you more HP. If you wanted to make this (these?) build(s) food dependent for Coil accuracy cap there's room for improvement in the damage department; food for thought.