Jersey may be such a small island, but you certainly cannot see and appreciate it properly during the time that the tour allows. I can guarantee that you will be back, because the four full days, sorry two days you spend on Jersey wont be enough, you need at least a week to visit all the places.
If any one from JY was taking notes, Drop the Guernsey day trip and have its as an optional add at the end on for a couple of days. The same ferry that takes you back and forth from Poole stops in Guernsey on the way - it takes you there on the day trip as well so should be easy to arrange and combine the two, and you would also get the opportunity to visit Sark and St Malo.
Lucia, a little tip in case you see this. I don't know how your sea legs are, but the crossing between the islands can get rough and very choppy especially between the two islands. If you have one of those wristbands or tablets take them with you. and bag yourselves some genuine jersey royals to take home they have just come into season.
