Personally I'd swap the 90 for the 110 - a lot lighter, as bright as you need and you don't need a centre filter.
However, then you'd had a spacing issue between 110 and 150 which would probably mean swapping the 150 for a 180..
I have the 110XL and have ended up with the following kits.
lightweight long hike kit
110XL, 200 Nikkor M, 300 Nikkor M
short hike kit
75 Rod Gran g/6.8, 110XL, 150 Sironar S, 240 Fuji A, 360/500 Nikkor T-ED
bells and whistles
58XL, 75 Rod Gran g/6.8, 110XL, 150 Sironar S, 200M, 240 Fuji A, 300 Nikkor M, 360/500 Nikkor T-ED
The 110 is such a nice lens that I woudln't ever want to get rid of it.