I can help with some of that.
To remove when someone changes their nickname. Options - IRC - click Events button - change Nicks to Hide
There is no option for aligning the nicks/text in the way xchat does. That could be scripted but it'd be a pain to do and make it look good.
on ^*:text:*:#:{ echo $color(normal) -mt $chan $+(,$nick($chan,$nick).color,$nick,) $1- | halt }
that will bypass the normal line format and do nick text
