This may be a very basic question. Is there a way to change the number of default rows/records show for a project? I almost always want it to be 25, and while it doesn't take that long to click it would be nice to just set it and forget it.
Is this something I could do as a preference, rather than editing the base code?
I did not try if this influences the default value, but there seems to be a Setting to set the different values: Running OpenRefine | OpenRefine
Not so basic as you might think 
Here is a list of preferences that you can configure in OpenRefine: Running OpenRefine | OpenRefine
One of them is ui.browsing.pageSize, where you can configure the available page sizes to choose from. For example [1,5,10,25,50,100 ].
Currently the value 10 is used, except for lists of page sizes, where the smallest value is > 10. Then the smallest value in the list is used.
So you could for example use [25,50,100] as page sizes and then 25 would be used as default.
But you loose the ability to paginate smaller values.