Good information, now that I'm here and still trying to acquire my live aboard, we've had an opportunity to check out the places you've mentioned. One this is certain, the cost is much more affordable here. Over 20/ft in Miami!! Much better here. Of course your cruising ground isn't as great but I'm not going to complain. The ratio of cruising to day sailing and short trips is still to low to justify the cost for me.
Check out Portofino. They are dockominiums, but many for lease. There was a number dumped by a single owner the past couple years, so you might find a good deal. The parking situation is good as long as you get the right slip, and marina is gated.
The best draft marina in Clear Lake/Kemah is Boardwalk, though I would not want to keep my boat there full time for obvious reasons. Southshore is too far in for a sailboat and a bit of a party place. Seabrook is good, and a little (I say little) easier to commute into Houston as NASA Road 1 is faster to 45 and closer to the bridge for the back way. with the exception of Portifino and Boardwalk.
Bayland is new, but not a great location for a liveaboard with nothing around, and you have to fight with the shipping channel where Kemah/Clear Lake there is good day sailing in the bay before hitting the shipping channel. Also not in the best part of town.
Harborwalk is a very nice Marina except the tugs will shoal in the entrance. You would think looking at a map that it would be a good candidate for commute, but the back road to get there is VERY long. There are also nothing around it. Did I mention the lonely road in is long?
Watergate is nice and probably the best family friendly marina with two pools, tennis courts, and not too far in. Waterford is very nice as well and you will find a great deal of people cruising were last based in Waterford.
Galveston should be avoided unless you are retired or work on the island and there are only a couple marinas over there anyway.
Be sure to join the Texas Mariners Cruising Association and you will get the lay of the land (water) in short order as they have many cruises and active members who know the bay very well.
Lakewood Yacht Club is my choice if you are into the Yacht Club scene and lifestyle. They have a number of slips and great facilities.
As a working liveaboard, parking and location of showers is important. Make sure to check how far as all of the marinas there are slips where it is a hike.
There are a couple of services that will come to your slip and pump your holding tank, worth every penny as there are fewer pump outs than you would think in Clear Lake. Without naming names, I liked the one with the Red Fish.
Be it LA, Dallas, Houston, Chicago, etc. you usually figure out in short order that driving 15 miles out of your way may get you to work much faster, and it is just the price you pay.
You will have a love/hate relationship with Houston.
I hate to let out the secret, but from a cost of living standpoint for living aboard and salaries in Houston, there is no better place in the country right now.
Welcome to Texas.