Reti beginner mistakes

Here are some dumb mistakes I've made after recently starting to learning the Reti opening. Any other mistakes or possible traps one should be aware of?

4.e3 or 4.Qc2 puts additional pressure on c4 and Black can't add to it's defense.

We encountered this recently in a vote chess game and we played 4.e3 and then followed with 5.Nxc4 which was a mistake. We should have played 5.Bxc4.
https://www.chess.com/votechess/game/169140?activePagination=archive&mv=2&san=e3

For myself I would prefer 4.Qc2 because after 5.Nxc4 I like to play the knight to e3.
https://www.chess.com/clubs/forum/view/1nf3-d5-2c4-dxc4-3na3

A lot of tricks from QGA also work for black in the Reti Accepted, which is conceptually very similar.  My preference comes from Open Catalan themes:  3Na3 Be6 4Ne5, where Qa4+ is still in your pocket if necessary.  It can get very tricky for black if he keeps trying to hold the pawn, for example 4...b5 5Nxb5 Qd5 6Nxc7+, 4...Qd4 5Nexc4 5Bxc4 e3 6Bxf1 exd4 (a couple cheapies I remember getting in club games).  The e5 knight will usually make the first capture on c4.  Of course the soundest lines will be thematically similar to QGA, like 3e4/3e3.  If you are comfortable in the QGA, you will eventually be able to transpose.  3Na3 Be6 4Qc2 is a good calm line, though e4/e3 is pretty much forced if black brings the queen to d5--once he's played Be6, you have to expect he'll sell out completely to protect that c4 pawn.