benzene ring vs thiophene ring

[BabyGurl3171]

What exactly is the difference between the benzene ring and a thiophene ring in Etizolam? I know it makes it a thienodiazepine rather than a benzo, but wth is the difference?
Also, would it be safe to continue usin AD's while takin Etizolam bc it has antidepressant properties that blocks the turnover of norepinephrine and 5-HT?
Wasn't sure if I should ask here or ADD...