If you want straps, but are umming and ahhing what about different style of straps. I was going to add little cap beaded organza sleeves to one of the dresses I tried on, or what about a one shoulder strap.
I am not a fan of strapless either, however it does look good on you. I am having a one shoulder (same reasons, SIL, best friend, other friend all had strapless and I want to be different), although am not a fan of spaghetti straps. Have a look at different styles of 'strapped' dresses to get inspiration, as they can add most styles to any dress.
Also halternecks are a preference, I dont personally like them.
However, if you think you will match your bridesmaids and you like spaghetti straps then I say 'Go with the straps'. xx