So, you're thinking of seeing The Lion King in London's Lyceum theater and you're wondering which seats you should get?
We went to see The Lion King yesterday, Oct 26, 2016 sitting on G9 and G10 in the stalls. Not bad seats indeed when you consider that you sit close to the stage being able to see the facial expressions of the characters throughout the show. The benefit of sitting close to the aisle is that the characters are passing and standing next to you at some points of the show.
With all that being said I wouldn't pick those seats again however because of two things. First, it's still to far away from the stage and second the audibility which is hard to believe kind of poor. It takes effort to follow along because many of the dialogs and even some singing seem to quite.
So my recommendation is to take the third, maximum fourth row of the middle section of the stalls. Why this recommendation? Those tickets cost the same as stalls G9 and G10 but allow you a better view of the facial expressions of the characters as good as possible. I also hope that you can hear better as the accustics of the Lyceum Theater is rather underwhelming.
After having seen The Lion King both in New York and London and I recommend seeing it in New York.