dddd

Those hybrid bikes have very good geometry for CX and are extremely durable, if heavy.

The stock shifters on that bike should already be indexing, and I'm not sure of what benefit it would be to switch bars, especially since the stem length and shifters would likely neet to be changed as well.
There's still time to get in a CX race or two, but this late in the season it would seem a waste of resources to do a lot of changes. I agree that clipless pedals make a huge difference for any kind of bike racing, and can be carried over to a better bike later on if you like the sport.

Tires and tire pressure can do a lot to suit a bike to the particular local terrain. It helps to get in as many practice laps as possible, both to learn the course and get the bike setup (incl. tire pressure). Most races allow doing practice laps during one of the other, earlier classes racing (even if you're not yet registered to race) which can help you decide if you want to enter a particular event.

Cyclocross is a blast because it's a relatively short, closed-course race, which means you get very familiar with the terrain as the race wears on.
After the manic first half lap, it settles into a fitness contest just like road or XC racing or even running.
Races are typically 30, 45 and 60 minutes for the beginner, B and A classes, with each lap being perhaps 5-8 minutes in length.