You're very welcome! I know the area quite well, just haven't driven in this neck of the woods for awhile. Richardson has older pockets (1950s ranch-style homes) and newer pockets--but many of the new neighborhoods still follow that alley-design, with a few odd homes here and there without rear alley access, and a few with front-entry garages.
It is a busy place, even though considered a 'bedroom community' to Dallas - there are several colleges that attract young adults (UTD, Richland, etc.) and the area also has had many businesses in the IT field. These college areas may be more apt to have security cams, but it's hard to tell (for me at least) which other centers would be using that technology. Guessing like any other city it would depend on the crime stats for a particular part of town. I'm really wondering if the driver of that Acura stopped to think about security cams, though. After reading and pondering some more today about that "whizzing" car, I've come to the conclusion that that departure at 4:00am may have been the driver simply 'getting the heck out of Dodge.' ASAP. And the fastest route out and away from that house and neighborhood would hands down be taking Centennial west to Central Expressway (a 5-6 minute drive at most, maybe less at that early hour).
Continuing that theory, once arriving at Central, he'd either fly north at 70mph-plus, or he'd go south.
So here are some options:
HEADING NORTH:
1) 75/Central Expy north, to McKinney and beyond
PRO: it's a straight shoot, no stopping until you get to the boonies
CON: it's a looong trip, even at that hour (McKinney is 22 miles north, and the boonies don't start until after that; familiarity with hiding spots?)
2) North a short while on 75/Central, then exit Pres Geo Bush Tnpk (going east or west)
PRO: fast, no stops on either road; terrain with some trees, woods, and creeks either direction
CONS: toll/license plate cameras on Pres Geo Bush Tnpk both directions
OR SOUTH:
3) take 75/Central south to downtown Dallas; keep going south right on out of the city via another hwy
PRO: fast, no stopping
CON: takes you through dense, pricey, well-patroled University Park/Highland Park with some very bored LE; risky dumping until you're south of Dallas (and south Dallas carries its own risks in the middle of the night)
4) south a few miles on 75/Central then exit onto 635/LBJ going EAST:
PROS: Fast, no stopping; going east on LBJ takes you through terrain with lots of trees, woods, and creeks; eventually hooking up with 30E can take you out to more semi-rural areas just west of and including Lake Ray Hubbard
CONS: ? (familiarity with hiding spots?)
5) south a few miles on 75/Central, then exit 635/LBJ going WEST:
PROS: fast, no stopping; takes you right out the LasColinas/IRVING - it's a 16-mile (shorter) trip to familiar territory
CON: none, if you stay on 635W and don't merge onto the new "Interstate 635 TEXpress" (which has tolls)
After writing this out and seeing how relatively short the round trip to Irving would be, I'm really wondering. It's been reported that WM had contacts there (work and church), so he would likely have had some degree of familiarity with the route (more so than others).