If you are holding back to level your talents, work on your honor. Getting to Imperial Commander is a HUGE boost to BR (a good 1k boost over High Commander). If you finish the Insignias needed for your lvl 60 gear, start working on buying the level 70 legendary tokens from insignias for your 70 gear. I had finished 2 stacks of level 70 tokens (50 tokens total) before I reached level 70. Outside buying your weekly medalion, your level 60 tokens and your level 70 tokens are a big priority. After that, you can spurge and use them to buy stamina flasks and XP books.
I probably learned this the hard way, but skip either the lvl 60 rings set or jewel set (one or the other, but not both) and get at least the level 70 version instead before hitting 70; preferably with the tokens needed to upgrade them. The level 70 normal is a tad worse than the lvl 60 legendary; with 1 less socket each, but you gain in time lost. Due to me go for full 8/8 level 60 gear tacked on a good 2-3 months to my farming of gear (damn slow Crypt token generation).
I would suggest do NOT put much into actual talents before level 70 (maybe 4 at most). Focus mostly on HS. If you are HS 66 by the time you reach level 69, then you can get a good chunk of the PvPers in the 70-75 bracket.
Finally once you have all your level 60 gear fully upgrade, synthesize your lvl 60 loids into lvl 70 loids. Getting you a nice leg up for when you get to level 70 and not have to farm as many loids. Also in that veign, start purchasing the lvl 70 stones from the guild store. Keeping the exact same number of loids to stones helps in the long run. If you buy more, that is fine. You need a good 1600 of each to get fully upgraded in lvl 70 gear. I had about 150 lvl 70 Loids and stones before I reached level 70 so that save me a good week and a half.