Actually the series is so short. Each episodes doesn't exceed in 20 mins. I think it is intended to just show the very summary of what happened after 3 years (like Book and Frame being married, Lukmo and his partner are still together and the hardships of TeeFuse couple in their LDR). If you are an MIR fan you will truly appreciate the efforts they spent here. Yes, the story is kind of messed up and the pacing is very fast. But what I value is the nostalgic feeling the series brought me.

In terms of improvements, i think they are still awkward to engage in kissing ( or maybe their kissing scene is really intended to be that way). I saw some of their acting that might make the viewer feel awkward because the some of actings are kind of stiff. Specially when they focused the camera to fuse when he is trying to make himself cry. On the other hand both actors did improve since the MIR 2. Especially Tee i already got the feeling that something's going to happen with their relationship when Tee first showed up.

Again, if you really are fond with MIR you should watch it it will bring you nostalgia.