What action should the pilot of a twin take when he comes across a microlight in front of him in a busy circuit?
A pilot with good SA will have allowed for this when joining and spaced himself accordingly, if he still finds himself close up behind then he should go around. Just because you are in a faster machine you do not have the right to push in front.
As far as straight in approaches and non standard joins goes, no problem IF you can fit into the traffic without getting in anyone elses way, this needs good SA and unfortunately too many people are not capeable!