Events. Sometimes I like to use a lot of relay events, I wish that you could easily copy and paste a line of event individually. Also, when you have events set up and want to change events from self to NamedBrick, it would be nice if upon that change, the later part of the event after the Self or NamedBrick section don't delete as sometimes, I want to keep the later part of the event, but change something closer to the beginning of the line of events.
It would also be nice if the engine was optimised to allow shaders on systems with an integrated graphics card so that more people can run shaders and stuff like that.
It would also be nice if you could have greater control over trust, sometimes I want people to use events on my bricks, but not allowed to build on my bricks.
DEFINITELY what needs to be done in Blockland is to have a dedicated RTB style chat thing integrated within the game. As back in RTB, I found that I could make a lot of friends directly in game rather than having to faf about on the forums etc... finding peeps to play with. It was also nice to see what add ons people were using. I don't mind about any other points I made, but seriously, a new RTB chat thing needs to happen in game!!!