Chain guard?

I am not sure why you would not be comfortable using your large chain ring. If your front derailleur limit is properly adjusted your chain should not fall off. If you are wearing long loose pants they will come into contact with the chain while you are pedaling if you have this guard or not. I would just remove it and leave well enough alone. You do have a few options available to you which you posted and this is your bike so you should do what makes you comfortable.

The vast majority of road bikes, cross bikes, and hybrids, as well as more than a lot of mountain bikes come without any guard like that, and they work just fine. As said above, all that matters is that the front derailleur limits are set correctly.

I had a problem with my nephew's Huffy a couple of years ago with a broken chain ring guard. I thought it was just decoration but as it turned out, the adjustment of the FD was so sloppy that it either would not shift to the large ring or it would over run the large ring. There was no middle ground. Even though it was a no-name FD, you would have thought that there was an adjustment point where it would work without the guard, but it wouldn't. So I made a replacement guard out of an old frisbee and he is still riding it.

Thanks for the replies.

I will feel better if it had a guard on it. I am going to make one from a plastic plate.
Simple ring with some spacers.

It shifts great, never had the least bit of anything but good shifts. It has Shimano shifters.
I am sure they are not top of the line shifters. It is a $150 Walmart bike I bought wreaked
and fixed it up. It is a 2010 model, manufactured in Feb.