The problem is, the UFA market next season is rather thin. The only bona fide star goaltender available is Connor Hellebuyck. If he is taken off the table via trade or if the cost of signing him is too high(which it likely will be), the drop off in talent is significant. The best goalies available after Hellebuyck are Pavel Francouz, Alex Nedelkjovic, Cam Talbot, and Marc André Fleury.
Francouz is a good goaltender, but unproven as a true number one thanks to injury issues. Nedelkjovic has potential, but hasn't shown consistency since leaving Carolina. As for Talbot and Fleury, time waits for no man, both goaltenders are in the twilight of their careers and far from being long-term solutions.
As for Samsonov himself, his season with the Leafs was impressive. Nearly unbeatable at home, the Russian netminder posted a strong .919sv% in 42 games this past season. By advanced metrics, Samsonov saved 17.39 goals above expected. On high danger shots, Samsonov's .882sv% was the best in the NHL among goaltenders who played 10 games or more. Most importantly, he became the first goaltender since Ed Belfour to lead the Leafs out of the first round of the playoffs.
The best option the Leafs have is to find a way to keep the tandem of Samsonov and Woll. At just 26 years old, Samsonov is just entering his prime. He would be much cheaper than Hellebuyck, and a far better option than any of the other pending UFA goaltenders.