I don't know what bladegrips you have (MicroHeli CNC i suppose?) but the weight itself isn't that much of an issue.
(Although they are heavier than what they can/should be)

My heli has all alloy and batteries twice the weight of stock lipo's and it still runs fine!
I haven't done anything to save weight yet , waiting on parts to do so...

Running powerfull batts is always a good idea!