I'm more or less in agreement with the previous comments. Starting off with multiple brands in parallel would increase your work load while fracturing your audience. We do see companies operating a hierarchical brand structure -- i.e. many individual brands beneath an overarching company brand umbrella. However, that's usually the result of acquisitions, mergers, spinoffs, and new launches over time. In most cases it's unwise to aim for that initially.

Better to find a brand identity that showcases the full diversity of your travel offerings.

Keep in mind that one brand can branch out in multiple marketing directions. One brand can be discovered in many different ways and places -- each appropriate to the business component in question.