Even though i leveled out of blitz a while back, when i had to use my BB1 in GB2 i can vouche that It. Is. Terrible.
I like the idea of having raised to BB2, but then at the asme time think about the DD,CL that while have a hard time competing with BB1s already, will now have to deal with BB2's.

On the other hand, remember blitzkrieg is basically to get you used to gameplay style, and how to properly control your ship/guns. Introducing BB2s to a game mode where new players have just started, would probably end up making them not wanting to play because now Blitz, and GB are too hard for them. Just saying from you and my point of view it would be easier and fun, but we also have to account for the new players that will have to cope with Ships that they would not even stand a chance against.

Imagine a BB2 Fuso in Blitz. 6 R slots. Each with dual 14'' that a volley of 12. 14'' rounds per 10 seconds really.

leave blitz alone .....

revamp the GB1 mode to give slightly better XP than GB2 and then CAP that mode at lvl 90 ...
this allows the CV and BB 1-3 a special room to learn in before the free-for-all melee of GB2's

Any BB2 can AW well above a FF/DD/CL/CA capabilities

L variants of BB2 guns can shoot well beyond the edge of the sandbox and downgrading to D guns can 1shot anything below BB with decent reload.

you can hit 500-600 SD even with a messed up crew. 900 was possible for MN in current blitz for some people and it will only get easier.

People will only learn to mount torps on their BB2 ( some with 10+ T slots). and cv will not learn how to even use ftrs till they are t3.

talking about nations for this, any US BB2 can mount 12x 14" guns as the fuso and ise or even 8x16". And with this lvl increase, people can bring in PBB and EBB 1 and 2.

while raising the cap would have allowed me to continue in my alaska and single handedly wipe out the whole opposing side (very fun :P) I have to say no.