It's not a matter of having too many good players on one team, you cannot sustain having multiple firsts and seconds ever year because eventually you will have to pay all of them at the same time. This is why trading draft capital is a good thing from time to time.
The Patriots are master's of this. When they have a lot of picks, they will move back into the following year or package them to move up. When they cheat and get stripped, they trade a superstar to get a pick (okay, that was for fun). It's less contacts to pay. Continually trading down is illogical from a contractual standpoint. You can only build so much draft capital before it's not helping you. You need to use it to move up.
If you add another first or second, it should not be in this draft.