I only tried Vi a few times, but what i accidentally found out was this descent build, which i havent finished yet, since it ended before i got to finish buying items.
But the outcome of this build was amazing, it is a bit of a late build, and it was tried out on bot lane, with a teammate.

Right, so the reason why I chose EXCESSIVE FORCE (E) is because of it's great starting damage.
Since you can stock up to 2 shots at the very start, it will give you an advantage since what i did, i tried to get 2 enemies in one line behind it, so i did damage to Minions + Champs

Another weird choice might be dorans blade, but it's not, because you do benefit so much from it (did try boots and 3hp potions for the first choice, was really bad potions gone - no more hp).

Third and last weird choice could be runes, i didnt really have any other great runes for this champ, so i just chose a basic, attack speed is good for most champs, especially with this build, since with this combo you get so much lifesteal with the item choice.

Masteries are standart, and actually proved to be quite good, didn't really think there was anything wrong with it, so i just left them as they are.

If you actually do try out this build, you will see, that after getting RAVENOUS HYDRA your damage, and survivability increases so much, with all the lifesteal and item skill activation every 10 seconds, so quick to kill all the minions or monsters and get your hp back from a 100 to 1500 is just mere seconds if you have a crowd lined up, or just in the jungle.

If you do like this build, just vote, i Might do a bit more detailed build in the future. Thank you.