I don't honestly see the draw for Corsica going to such lengths to assert its independence from Genoa, only to end up as a part of Italy - even if it ends up as the notional founder of a united Italian state.
For one, it must be kept in mind that without the Napoleonic era, it's unlikely Italian pan-nationalism would have developed on nearly the same lines as it did in our time. For the other, it's also fairly certain that Corsica spearheading Italian unification wouldn't save it from being overshadowed by the more populous and economically powerful regions of a united Italy, leading it to be doomed to neglect and assimilation by the mainland. It was the royal house of Scotland that ended up securing a union with the Kingdom of England; that did not prevent the monarchs from moving their capitol to London and establishing a state hierarchy dominated by England.
Some form of federated union between Corsica and Sardinia might be interesting, but would be hard to handle in a way that would be satisfactory and representative for all its inhabitants; there are Corsican-speakers on the north of Sardinia, but it has nearly five times as much population as Corsica does at present, not to mention the language disparity between the Sards and Corsicans themselves. Still, the ideals of the Theodoran system might appeal to them, at least moreso than the alienation seen under the Savoyards. A union of the two islands would also be ideally situated to be very powerful in Mediterranean commerce and strategic positioning.
Overall, I'd prefer to see not Corsica as the founder of a united Italy, or a part of Italy, but an inspiration of sorts for mainland Italians should a pan-national movement develop. A pan-national movement founded by someone inspired by Theodore's liberation of the people from Genoese tyranny, acknowledging the diversity of the Italian peoples and trying to bring them together rather than bind them into one, would be quite cool to see.