Availability in the summer starts to get really tight around the very last week of June and stays that way until mid-August. I have not checked for points availability recently at either. Depending on when I'm going up there, I might use one of my weeks or just rent from a 3rd party rental company.
The Grand Residence and Timber Lodge are adjacent to one another with the Heavenly Gondola right in between. So, that which is close to Timber is close to Grand Residence. There are even tunnels underground that connect the complexes buildings and they share some staff.
I thought that the children's activities were consolidated. So anything available for Timber guests was available for the Grand Residence guests. The Grand Residence Children's Activity coordinators are excellent.
Grand Residence has more restaurants right in the building including a couple of the top rated restaurants in the Tahoe area. I always make a point to eat at Azul, Base Camp Pizza, Driftwood Cafe, and Kalani's at least once. And, I have eaten at Fire + Ice 9 or 10 times and have never had a bad experience.
Parts of the Grand Residence buildings can be a bit noisy. Especially the back building that faces Gun Barrel Tavern and Base Camp Pizza. That noise would also be heard on the gondola side of Timber, though. But, all outdoor bands and music are supposed to cease at 10pm. Another reason that parts of the Grand Residence might be noisy is that most all units have balconies and people often leave their doors open.
The rooms at the Grand Residence tend to be a bit bigger than Timber Lodge; at least the ones that I have been in. And, the balconies are nice though different units balcony sizes vary widely. A 1-bedroom I stayed in had a balcony big enough for 8 or 9 people to stand around on while a 3-bedroom had only a tiny balcony off of the master bedroom.
The rooms at Timber Lodge have washers and driers while the Grand Residence has laundry rooms spread out around the building.
And, yes, the Grand Residence has a wide variety of floor plans. 55 different floor plans, if I recall correctly. But most area spacious and nicely laid out.