By Tai Tam, are you referring to Redhill or Pacific View/ The Manhattan? Redhill seems more isolated to me, but I have friends there who love the relative quiet. All three places are quite pretty.
Commute to Central: you can definitely get to Central (before or after traffic) in 20 minutes from Red Hill, but 30-45+ minutes is more realistic during the day (after 7am and before about 8pm). Traffic definitely affects the commute time during the day, at night it really is only 20 minutes. If you are referring to Pacific View/ Manhattan, add just under 5 minutes. These commute times assume taking the route to Chai Wan and then the highway to Central. It will be a bit longer if you go to Stanley and take a bus over the hill or through Aberdeen tunnel.
Facilities for kids: Each of these developments has facilities for kids, including playgrounds and nice pools. Pacific View has an indoor pool also. The outdoor pools at Redhill are more resort-like (waterfalls, slide, etc). There are several preschools/ formal playgroups at Redhill plaza. There are also preschools in Repulse Bay.
Shuttle bus: Each development has shuttle busses to Stanley and Central. The shuttles to Stanley depart much more frequently than the shuttles to Central.
City bus/ mini-bus: You will also have frequent number 16 minibusses to Chai Wan MTR station passing each location. From Chai Wan you can get around to the rest of the north side of the island/ Kowloon, etc. pretty efficiently. Once in Stanley you also have a number of city busses going to various locations in HK.
Commute to Stanley: Pacific View/ Manhattan are about 5 minutes from Stanley by bus/ taxi, the drive from Redhill to Stanley is a few minutes longer. The big difference is that walking from Pacific View/ Manhattan to Stanley is possible (it takes about 15 minutes) whereas you cannot safely walk from Redhill to Stanley (no sidewalks along a fair bit of the route). Stanley has an indoor playroom for young (under 5) children, an outdoor playground and beaches, in addition to restaurants, grocery stores and a nicely remodled plaza hopefully re-opening soon.
Beach: In addition to Stanley's beaches, Pacific View/ Manhattan and Redhill each have beaches within walking distance. Each complex also has sea views from most apartments.
Country park access: Directly across the street from Redhill, no need for a taxi. Will need a short (under 5 minute) cab ride from Pacific View/ Manhattan because there are no sidewalks on the way there.
Other stuff: Each complex will have plenty of families with children of various ages, a mix of local and expat families and some stay at home moms. Each complex has a small room for a domestic helper, even in two bedroom units. Most units in each building will come with one car park space also.