Advice Feedback on My 10-Day Bulgaria Itinerary

I'm planning a 10-day trip to Bulgaria and would love some feedback on my itinerary. Here's what I have so far: Day 1 – London to Bucharest, Day 2 – Bucharest, Day 3 – Bucharest to Veliko Tarnovo, Day 4 – Veliko Tarnovo... I'm looking for advice on must-see spots, hidden gems, and any adjustments you'd recommend to make the most out of my trip. Also, any tips on local cuisine or cultural experiences would be greatly appreciated!