I have built many strip boats. I would NOT work with strips of inconsistent thickness. You will make this job much harder for yourself if you do.

Inconsistent strip thickness will make it harder to mill bead and cove and align edges for a good joints.

This will lead to more sanding and fairing of the uneven surfaces inside and out making it highly likely (especially if this is your first boat) that you will have an irregular surface.

Irregular strips will compound every future step of the work process.

It's like putting on dress shoes for a race when everyone else is wearing sneakers. Sure you can do it. You'll blame your poor performance on inexperience and that will be true to some extent. You won't even know the difference until you run a race with running shoes.

You can resaw the inconsistent strips you've already cut with the saw set-up I described above. Just add a couple featherboards pressing the strips from the side into the fence.

I use only 3/16" strips on all my boats.

Take all the time you need now to cut consistent strips. Your time cannot be better spent and will go miles toward producing a fine boat.

All the best,
Rob