Regarding CGs in Bakka, well I think that the Avenger would probably be ideal for this fleet, exemplifying both the big guns that the lobby was famous for as well as justifying the backlash against them (it's too slow, too short ranged, can be outclassed by AC, etc).
As for the turret issue, well I have always argued that the solution to having no carriers was to allow more turrets. Others have argued that this was not enough and we needed convoluted (and rubbish) FDT rules and dedicated fleet carriers (Jovian) and whatnot. It's strange to see the argument now that extra turrets is actually OP.
Nevertheless, it may be the case. However, I notice that you did not boost the base turret level of the battleships or escorts, only the cruisers and light cruisers. Presumably you could also elect to not boost the base turret level of the grand cruisers.
Also, you have the rule "all ships may purchase an extra turret for +5 pts". This seems to include escorts, which I would personally exclude from this. So I'd adjust it to read "all capital ships ...", etc. A further adjustment could be "all light cruisers, cruisers and battlecruisers may purchase ...", etc. This would further limit the Bakka dominance over ordnance if this is perceived to be too strong. Of course, it would allow for 4 turret cruisers and battlecruisers while allowing only 3 turret grand cruisers. Not to mention that battleships would have no further protection than cruisers against bombers in this case.
Alternatively, you could alter the rule to say that CLs, CAs and CBs can buy a turret at +5 pts and CGs and BBs can buy one at +10 pts. This would at least make those more durable ships pay for their protection.