Off-road/Dual Sport gearing question

Hey guys, so I have an 18 KLX 250. I am 34 and looking to try my hand at maybe a small off road race this year (first time racing in my life). I know the bike isn't ideal for off road racing but it's what I have and would like to give it a go. I currently have only used it for commuting, and would like to continue commuting with it and was wondering if I should change my gearing for said off road race or if I should keep it stock. It just doesnt seem to be snappy enough in the acceleration dept. for tight trail riding but at the same time its perfectly fine-for me- for on road use.

So realistically I guess I have two questions here:

1) Should I change the gearing for off road use, what might be ideal? Stock its got a 14 tooth counter shaft sprocket and a 42 tooth rear sprocket.

2) Is there a gear ratio that works well for both off road-tight trail as well as comfortable on road? Top speed isn't an issue as I rarely go above 50 on it during my commute. Thanks for reading, and thanks in advance for any advice!