Of course dressing well in general will increase your value.

I have noticed that when I wear a nice fitted slim fit blazer I get way more IOI's. For some reason I also feel very confident when I wear one.

You don't always need a dress shirt, even wearing a blazer over a tee shirt will give you a presence.

During winter months I will usually wear a dress shirt and summer tee shirt with light blazer. Always fitted. Try it.