[WARNING] Your question is a very good one. Furthermore, it runs deeper than many of the passionate elements (e.g. "athletic gear") touched on by many within this thread. (Which are all great points)
The key word in your post is "brand." This has been a challenge for MSU for decades. Logos, taglines, and the indicia come and go -- sometimes it evolves for better -- sometimes for worse.
We are living in a time that has been shaped by a considerable number of univeristies using athletics "front and center" for recruiting to raise enrollment by drawing from a national audience. The majority of a university's budget is AIS -- "asses in seats." A competitive athletics program helps that tremedously by serving as a form of "passive" advertising for a university on a national level.
When you say "marketing," I interpret that as messaging, and my many questions would center around the following:
* What is the message MSU wants to send? (Value? JCareer? Innovation? Athetics?)
* What is the message it is CURRENTLY sending?
* For whom is that message intended or what audience is targeted? (Propsective students nationally? Transfer students? Alumni? All of the above?)
* What metrics are be used to determine if the message is effective in reaching, resonating, and getting a response from the target audience? (This is much easier said than done)
* Does the marketing plan align with the mission, vision, values, and strategic plan of the university?
* Is the strategic plan of the univeristy a good plan in today's environment?
If MSU is the place where "Bubba and Susie" in the State of Mississippi can get a quality college degree that is relatively inexpensive to other univeristies; AND, if MSU is the place that wants to be fiscally conservative and make sure that the status quo isn't jeopordized...then you will likely continue to be disappointed with MSU's overall marketing efforts. You will see nothing transformative from MSU -- incremental improvements, at best.
I'm a firm believer that it is the students who drive the positive energy of university -- not the administration. When a university has messaging that energizes the sudent base, connects with prospective students, and also resonates with alumni who ALSO feed off that energy -- then you have a brand to build around.
Right now students are fair weather about a football game because...well... we don't win consistently. Worse, MSU has no tradition of winning in football. (I'm picking on football because it's the easiest to do in the context of this thread). Yes, you can look the Alabamas and the like, but those programs have National Championships and lifetime winning percentages MSU will never achieve.
I know this: Marketing is a hard job at any university -- especially these days. MSU is no exception. It's a job I wouldn't want because no fan base / alumni base will ever be fully satisfied with what you put out.