I did for several years while in college.
What is a realistic salary? like all sales positions there are huge ranges. It depends how hard you want to work everyday, the traffic/location of your store. The price point of the products you sell and your commission %, the relationships you build, and also what the economy looks like.
Is it commision based? yes
Do you find it stimulating? no
Is it a grind? yes
Are promotions out there for hard-working individuals? yes
Do most people like their job? yes, during the summer and nov-jan. Feb-May no
The good thing about retail sales is you can def make good money if you are in a great location. There are plenty of 1mil+ sellers who can take home 100k+. At Nordstrom #1 seller takes home around 250-300k. But if I were still in that industry I would def look toward management. Many people become complacent in their roles: SA's typically don't want to go join the entry level management ie assistant manager/dept manager/store manager because the first few rungs on the ladder the managers make less than the SAs.
If you get a college degree and work hard and do well as an SA you can easily become a manager within a year or start as an assistant manager if the company has one of those training programs. Within 5 years you can be a store manager. To go from store manager to a regional manager can take longer because sometimes people stay in their jobs forever, meaning you have to wait for them to retire or die. But if you are mobile and jump to other retailers or designers you can easily avoid this.