Merge or not

What would help you more, swift sparrow on another unit or 1HP 1spd more on flying Nino? Or even aerobatics on some defense team unit or someone like Laegjarn who can take a hit?

Do you use her frequently? Do you have a build in mind that you would like to have swift sparrow on? If only one of those questions answer is a Yes that should tell you my recommendation.

You can merge if you use her alot and maybe plan to plus 10 her. Swift sparrow is not really all that great since theres so many other options like life and death and fury 3 which do the same thing basically