Does not look bad from that angle.
A few things. Back thickness can take time as it slowly grows over the years. Mine was always wide enough, but until I was doing steady heavy deads, rows etc., over the years, it grew thicker/deeper.
Also, don't neglect power shrugs et al. as they can add to thickness and some upper & nice traps. It is not necessarily more or better exercises as much as it is consistency over time and heavy weight.
Keeping the waist slim also gives an appearance of wider shoulders etc.
It's getting there, just be patient ;-)