I know we all have a few suggestions for 4.0; here's mine:
• Better general interface, without those ugly blue window panes in existance right now
4.0 is almost entirely an interface upgrade, so this will definitely be there.
• Coolbar Toolbars in Dream Maker
Not sure what you mean there, but it sounds cool.
• I've noticed on games like Seika II that there is a glitch that causes blocks to appear around your char for a split second thats very annoying.
No idea. Sounds more like a bug to me, but fixable at some point.
• Maybe a new icon set for dm files and such
Ter13 has done some impressive icons for the programs themselves, and a little work toward new file icons. I'm looking forward to see what he comes up with.
• DS skins and definable in DM code (or just skins in general)
This is the heart of 4.0.
Lummox JR
No more than I'd expect a coherent argument. BYOND is primarily for making graphical games, and we're not talking about a full-featured image editor. BYOND supports those file formats, so it would be convenient to have a built-in editor for them. Imagine how annoying it would be if BYOND didn't have a built-in code editor. You could use a third party program for typing up the code, then switch back to DM to compile it, but I'd bet it would get quite annoying. I realize its the features like this that tack on kilobyte after kilobyte to BYOND's download size, but it just might be worth it.