In my experience (now more than 50 years old), the titration experiment is easier. What could go wrong? I remember in my class, one group of students got the base directly from the reagent bottle, rather than the specially prepared solution from the teacher. Consequently, they could not neutralize the solution practically no matter how much base was added. The solution to be titrated was far more concentrated to neutralize, but as long as you use the prepared solution by the teacher, you should be alright.
On the other hand, I think you will find the electrochemistry experiment far more interesting. (I am old now, so forgive me if I do not understand. I figure you are under 20.) Is it really important whether you get a 20/20 rather than say a 19/20 or 18/20. Maybe you can impress the chemistry teacher and get a really good letter of recommendation if you go far the harder experiment. Maybe your instructor will be more impressed and more easily grade the harder experiment. Of course, I cannot even be sure the gavanic cell is the harder experiment. The question really should be in which experiment will you learn more from.
PS, I found titration (in eleventh grade) as stock and trade for a practicing chemist, but I will never forget the excitement I got from electroplating a nail, (in fifth grade), although clearly, your chemistry class will be more advanced than that fifth grade experiment, which did not even require a write-up.
