There are several gauges in violin string, heavy, medium, thin etc.
I know the heavier the strings the louder the tone, but
- Does it affect the richness (complexity of overtones etc.) of the tone?
- Is it drastically harder to play?
- Can it be harmful for my fingers or compromise the sound using a set of heavy if my violin is balanced with 4 medium strings?
- Do the heavy strings have a longer durability and chance is they last longer?
Regarding the tension on the instrument fingerboard or neck, there is already a nice answer here.