I do agree that players can get confused with the way the new Journey Guide is laid out. The other prime example is that Rex is a requirement for the LV battles, but is not one of the prerequisites.
You need to click on the tiers to see what the requirements for each tier are, which are different than prerequisites. For example, the prerequisites for the Jedi Knight Revan Ancient Journey are just get to level 85. But just being level 85 isn't enough to play the tiers. You need specific characters.
If you absolutely cannot upgrade your ship now, my advice would be to save up as many crystals as possible for the next run. You can refresh the bonus tier 19 times at 999 crystals for extra shards, which will leave you 50 short of a 7*. You can then either wait a month or buy packs that are 1250 crystals for 10 shards. So for 25,231 crystals you can get 7* in one day.
Also, if you don't know the Malevolence + TIE fighter comp to beating Executor already, you can look that up and it can help you stay competitive in fleet arena for the next month.
