Unless a travel agent is working on his/her own, they aren't going to make 10%, because the agency will always take a cut.
I am a home-based agent for a store-front agency. I make 1/2 of the commission, the agency takes the rest. Because I am home-based, I am considered a sub-contractor, so I also pay my own taxes out of my commission. For example, say the cruise line pays $500 in commission, I am paid $250, then take out whatever my family's tax rate is for that year, and there you have it. Whether I worked 30 minutes on putting together a trip or a week, no matter the amount of calls or lack of calls or changes and redirection of plans, that is my pay (and no social security or insurance).
This works for me, I get to stay home with my family, my clients know I don't have regular office hours, so they love it, too. The pay is not much considering the hours I put in, but when a client gets home and tells me that they "just took the best vacation, thanks for making it happen", well, that's why I do this!
Other agencies may take a different percentage of commission, and some agents are paid hourly, not per commission. I will say, though, that if I have a client on a
DCL vacation, thanks to the higher commission, I will offer them something once they get on the cruise. It is harder to do on a lower end cruise line, as commissions are much less.
Also, the price of the cruise is not what the commission is based on. Each cruise line has "NCF", or non-commissionable fees. These are like service fees (or whatever non-explanation they give). More cruiselines are increasing their NCFs, thus decreasing what is available for commission.
If your travel agent is giving you money back or shipboard credit or whatever type of "thank you", stick with that person. That agent values your business, and you aren't just another paycheck to that agent.