Help with Master YI

Hey Guys,

So i am a master Yi main(Albeit not a very good one, Currently working on that)

Now i am finding an issue with the the current build with him in that it takes a while to be useful

What i normally do is save up for BF sword as my first purchase, which basically gives me a surge in power, but still it feels a bit underwhelming

Anyone got some suggestions/tips on how to not feel so useless early game(Again this could just be me)