Delayed engagement is sometimes low fluid, but old burnt fluid can cause it too. Beyond that, its wear and tear, if thats the case you will need at the very least a valve body rebuild. Worn bands and clutches can also cause delayed engagement.

Sorry to hear about the throttle body issue on that Focus, sounds to me like another failure of the drivers education program, you shouldn't have to learn how to handle and emergency after you've had a problem. Ford had an updated throttle body, the originals were made in Mexico, the revised design is made in England. Not sure how common of a problem that was, but Ford did address the problem.

A Maxx will not out accelerate a Porsche, especially not when you say "any" Porsche, trust me, a Malibu MAXX has got nothing on a Carrera GT. But a Maxx does have good power. Overall my Focus has been an excellent car, just like most the other Ford's I've owned. Crashing into a barrier will only set of the airbag is the radiator support gets bent enough to activate the sensor, if the car hit the barrier sideways, or on the back, the airbag won't deploy.

Heres a buying guide on an Aerostar. It is very unlikely you are gonna get a good trans no matter what you pay for it. Any Aerostar trans beyond 120,000 original miles is on borrowed time. Sure some go far longer than that, my Mom's '95 has over 200,000 on the original trans, al lot depends on how well it was maintained, but regardless, if you can budget in the minor upgrades to prevent a failure up front, you are going to have to rebuild or replace a trans in one sooner or later. So if the van is mechanically sound and well maintained, and the interior and exterior are in great shape, its probably worth it. Replace the fluid with new, the trans fluid is one of the most commonly neglected things. Sometimes that all it takes to make it behave. 1995 is a good year, thats the first year of the all electronic trans, which improved the reliability over the A4LD in the previous years by 50,000 miles or more. If the van still drives and engages, a valve body rebuild and a few minor tweaks can still make the trans last a long time for minimal investment.

Another note though, on this economy thread, I did not mention that I am not a light footed driver, and I am getting much better economy, so 11 mpg is just plain not a normal thing. Something is most definitely wrong.