Bicycle in spring

Hi ! I will come to Tromsø for work in one week, and I plan to take a few days off to do some hiking, both on foot and on a bicycle. I have several questions to plan this :

• Should I bring my snowshoes, or is there already not enough snow for it to be useful ?
• Is it safe to park a bike overnight in the street ?
• I plan on going to Nord-Lenangen by bike and come back on the express boat. Is it possible to board the boat with a bicycle ?
• What other day-trip on bicycle would you recommend ?

PS : A big thanks to this subreddit, I already found a lot of general information for my travel !