If you have an additional day, you can visit other places in Wayanad like Banasura Sagar Dam or spend time at the Lakkidi View Point.Similarly, you could spend more time exploring the backwaters and take a village tour or a cycling tour.
If you have less time, you can skip the Chembra Peak trek or reduce the time at Vembanad Lake. You can also opt for home-stays or budget-friendly hotels in Alappuzha to cut down on the costs of the houseboat.