I kinda think that any more than 40-45 mins on weights is an indication that you just haven't worked hard enough! Some people will say that if you've done weights you shouldn't have anything left in the tank for cardio afterwards but in reality, a lot of people do this and its not such a bad thing. Having said that, unless you have have an extremely challenging fat loss goal then 20-30 mins is plenty.
Agree that you need to schedule at least 1 proper rest day each week.
Lots of people do weights and cardio on alternate days, 3 days of each. You could then do a longer cardio session if thats what you enjoy. (Some have to be dragged kicking and screaming to cardio ....!)
So, you aren't that far off the mark as it happens, but maybe just cut back a little and make sure you have your rest