Uh, mix damage is far from OP. All of three items in the game give AP as well as AD. All having mixed damage does is allow for creative builds. In addition, Sami has all of two abilities that scale on AD, and one is pretty much just an autoattack modifier.
Speaking of which, did you read the effect? 100% AD scaling on something like that would be hilariously overpowered, as it gives her two attacks at a very high attack speed. I was hesitant to even put it at 40% on the fear that it would completely wreck face and make her a more frightening AD carry than AP carry.
Scrap barrier is indeed fairly powerful, if managed correctly. I was thinking of making it so it didn't stack. A potentially 1900 (+100% AP) strength shield after a full combo would be fairly tanky for a mage.
Ult wouldn't be difficult at all. Take Annie's pet, and then set up an array of buffs based on what spells Sami last cast. Easy.
Overall, what I was able to figure out from your ATROCIOUS post layout and grammar seems to imply that you don't seem to know much about what you're talking about. Hybrid ratios are neither inherently OP nor do they force a person into any particular lane. Sami's long range makes her much more adept at mid or even bot than top, as she doesn't make a great bruiser even with her shield.