Interesting. The most recent time I rode it was around 9:15 or so on a non EMH morning last week. There were 3 full trucks waiting to go from the loading dock, and the handicap-accessible truck that I was on got to enter in front of them. Then we waited behind several trucks to unload. For these trucks, the additional minutes were not spent observing animals, but on waiting time.
I want to state again- this is not a driver complaint. The OP specifically wonders if containing such an enormous portion of the park experience on this one ride has an effect on people's oppinion of AK. A subsequent poster mentions a common perception that AK is a 1/2 day park.
An enormous portion of the land area of AK can be seen in roughly 18 minutes. Yes, I think this does contribute to the perception that this is a 1/2 day park.
The safari IS the Animal Kingdom to me. I just love it! I think it would be even better if it were longer. I think if the queue was better people would be willing to wait longer in line.
I don't like the Simba 1 story line because the fake animals and trucks detract from the otherwise natural (or naturally disguised) setting. Seriously- they look borrowed from the Jungle Cruise, which is kitchy fun, not wild and natural.
Additionally, the frantic aspect of the Simba story line contributes to the rushed feeling of the safari- at least toward the end. The driver could be driving the same speed with some relaxing African music and it would change the feeling completely.
It's 18 minutes from Load to Unload. Load 3 (the wheelchair dock) has different times and operates independently of the other trucks.
The other option is to have people walk through the same areas that the safari truck takes you which returns us to the other complaint, the park requires too much walking.
Regarding the queue, I don't think for the average guest the quality of the queue has any bearing on their initial desire to partake in the attraction. Before Fastpass, KS regularly posted 90-120 minute waits in the morning and would traditionally die down to a walk on in the afternoon. While this has changed somewhat with the implementation of FP, the pattern still holds relatively true today.
I'm not sure in my 3 summers working there anyone said to me, "I'd love to go on Safaris, but that queue is so boring". While most of use have come to expect a E:E level queue, E:E is still the exception, not the rule.
Additionally, that franticness is, like you said, only the very last portion. Also, that area past the smashed gates would be empty regardless. It is all hidden infrastructure from there to the unload.
I don't think that the size of KS has anything to do with the perception of DAK as a 1/2 park. I think it is the expectation of the guest and the way Disney has shifted the focus over the past few years.
Moving away from animals and towards a traditional Disney experience has made the theme park based shortcomings of the park stand out more. There has to be a balance and I don't think DAK has quite found it yet.