'Doctor Who: Rebellion on Treasure Island' has an interesting idea of having Doctor Who mix with the in-universe land of fiction, in the form of pirates in this story, something that's been done since William Hartnell played the Doctor back in the mid-1960s, but this story really falls flat on its face in the end.
The story starts off interesting enough with the Doctor receiving a mysterious phone call and heading to 1756, where he and Clara find themselves confronted with Captain Trelawny, who informs our TARDIS duo of Treasure Island, but shortly after arriving the Doctor and Clara are separated and then a couple chapters later, Clara is basically just written out entirely. She's still around, but you could honestly remove or replace her with any other singular companion and nothing would change. It would be the exact same story.
The plot is just constantly jumping about and the story is filled with characters simply expositing what's happening or what they're doing all the time, which really gets grating, and a lot of the characters feel flat. The 11th Doctor specifically but he is a hard character to write considering just how much character Matt Smith flooded his incarnation with, but that doesn't make up for the rest of the cast; most just came across as stereotyped characters, which leads to some very stunted and lacklustre dialogue, in my opinion.
This story also suffers from the same issue I have with 'The Return of Robin Hood' by Paul Magrs, which has all the main crew forget everything at the end. The difference here, however, is that the reason why they must forget is shoehorned into the story itself.
As for the main characters, it starts with the Doctor and Clara, then we're introduced to River, then we basically lose Clara for the rest of the story, and then afterwards we're brought to 1831 and meet the Paternoster Gang, who then, in a way, replace Clara. But the problem is one character gets replaced with three and we're already halfway through the story by this point, and in the middle of all this character swapping, we get introduced to the villain of the story. And the villain isn't even that interesting or creative.
I personally feel this story would've worked a lot better, character-wise, had it been the Doctor and Clara arriving on the island, the Doctor getting taken, Clara then going to the Paternoster Gang or persuading the TARDIS to take her there to get help, them then coming back, freeing the Doctor, and then we go from there. It means you cut out the need for the memory loss and the self-inflicted paradox too, both of which were just unneeded in an already flooded story.
With the number of characters in this story, it really feels as if Bali Rai was trying to do fan service with some of these character meet-ups but then never does anything substantial with them. You had Clara and River meeting each other for the first time and did nothing with it despite there being quite a lot of potential chemistry in there.
I do think this book is readable, but I honestly wouldn't recommend it unless you're okay with reading a story with the 11th Doctor and his late era's team fighting an alien menace, and then in the background are some pirates, because that's what this story is in a nutshell.
Overall I give this story 2/5 stars. There are definitely better stories in this range you can read; this one is just a dud.