First of all, let me put your mind at rest.
I have had 2 holidays canceled & it turned out well both times. The first (years ago, firm called Intasun, gone bust now) was when we got off the plane (Rhodes) to be told that due to an overbooking we had to be put somewhere else. As there was 11 of us, this probably wasn't to easy for them & we got moved from a small basic hotel, to a really nice one

. Second time (Portland) was a week before leaving we were told our planned hotel (Spain) was closing early & they would have to move us, they offered me Loret de mar, I said not likely & ended up in Tennerife in a much better hotel, hotel in Spain paid £1,200, value of Tennerife holiday £2,200. Oh & we got a small amount of compensation too. I didn't pay a penny extra

.
So both times were good.
I don't know how things stand for you now, as you say as yet you have only paid deposit, does that mean you can have your deposit back & book elsewhere. Good bargaining tool.
I think if you pick a holiday of greater value you may not have to pay any extra

& might even get compensation too.
Why don't you go to the First Choice web site, put in your dates, places you would like, the amount of people & any requirements, like centeral location, good for kids ECT. See what they offer you. Make a list & post all of them on her & people can then say if they know of any that are good

or bad
Hope this helps
Kim