I have just posted an identical question so hopefully I should get some good advice. Can you let me know what combination you decided to go with in the end.

I would thoroughly recommend the roof inserts as we had these inserted in our last conservatory and they significantly reduced the heat and the glare in the summer and also helped to retain a little bit of the heat in the winter.

They are also relatively cheap to install by yourself or by a specialist (approx 750 pounds to be installed by a professional for a 5x4 conservatory.