I just hate the idea of "Spiders" being the name. There's a very weak connection to Cleveland baseball history (and no connection to this franchise), has nothing to do with Cleveland, and it's not intimidating to anyone other than those with arachnophobia.
Guardians, to me, is the way to go. Keep the colors, keep Block C (or bring back Crooked C), keep the uniform design - just change the script "Indians" on the chest of the home jerseys to "Guardians". You pretty much maintain the branding, which maintains a connection to the team we're cheering for now. It's got a unique connection to the city and the Guardians literally stand outside Progressive Field
It also turns what has become a negative team name into a positive one - guardians can be anyone...they are selfless, looking out for those who need help or safety.
Renaming the Indians the Cleveland Spiders with an all-new look would, to me, feel like starting over...almost like an expansion team. Shifting a tad toward Guardians and keeping so much of the identity we've all grown up to love is a better option to me.