The whale barrier might be lower than we think should STEEM go on a bull run - with the amount of STEEM being locked up in SP the float is small and the STEEM market is very, very tight. A run of 10x or 100x in market cap is completely possible if not probable over the next two years. There may be a lot of $10 - $100 votes to be had in the near future.
All that said, I think your idea is awesome and more categories with attendant whales would definitely bring in more talent and content. I'm surprised we aren't seeing some of the newly minted travel/photog dolphins and whales doing exactly what you are suggesting in the travel/intro sections. The whales dumped a huge amount of STEEM/SP/SD on a few of these (mostly) girls but I'm not yet seeing consistent upvoting by the pod.
higher STEEM price does not affect each whale's percentage of VESTS. Only their relative inactivity vs dolphins does. That is the math. And if whales are inactive, then the average awards will go down 90%+...
Also, without a more formalized system in place and without even any agreement as to the responsibility for the newly created travel dolphins, there is no assurance of continued success. That being said the "photography" tag is still consistently at the top. Realistically a single whale is still more influential than all the travel dolphinettes combined
Based on mathematical analysis of steemit, this is my recommendation to create feedbacks using the math to get hundreds or even thousands of speciality categories with the best content of anywhere else, that just happens to pay enough for a critical mass of authors in each category
like the old liquidity points system, if you take out the human factor the end result is just whatever the optimal math solution is