Roll-up window shades

[ttarpn]

I am not handy.

My situation:
--The back of my small (1200 sq ft) house faces south
--three almost floor to ceiling south-facing windows downstairs in the LR/DR.
--I don't use this room during the day.
--It has 3 large doorways open to the rest of the house.
--I live in RI.

After looking at a lot of diy projects to reflect summer heat out and absorb winter solar heat in, I'm wondering if switching out shades winter/summer might be a way for someone like me to get at least little help from the sun. Not very efficient, but better than nothing. I'd like your opinions on this.

For south-facing windows, 3 shades total. For all others, 1 shade only.

Winter heat-absorbing shades:
--closed in LR/DR during the day to absorb sun heat
--basic roll-up shades, black side facing out (the window glass)
--installed 3 inches down from the top of the windows leaving gap for rising hot air
--extending down, leaving a 3 inch gap at the bottom to suck in cooler air
--installed inside window frame
--removed entirely during spring/summer/fall

Switch out roll-up shades, 1 for winter, 1 for summer:
--for winter, just regular shades, color pale gray both sides
--Closed at night during the winter
--open during the day during winter
--for summer, reflective one side, facing out, pale gray inside
--closed during the day in summer
--both summer and winter, installed outside frame

For the rest of my windows (N, E, W exposures), same as winter shades--no switching out with summer shades.

Good plan? Almost useless plan? Tweakable plan?