I don't think it will make much difference which method you use and unless you plan to load your file on an iPad or iPhone, current hard drive capacities have grown to a point where such a small difference in file size that might occur between the two approaches is completely negligible.
Either way, you are storing a list of values in a single location: either a table or the definition of a value list--which could be seen as just a special kind of table. When you select a value, only the selected value is stored in the field of the table where you set up your field to use that value list. The exception is if you select multiple values--such as clicking multiple checkboxes, but then only the selected values are stored in the individual records of your table.
The more important distinctions between the two options have nothing to do with file size.
I use it for my inventories, so I do use it on my iPhone while traveling. It is not my primary method...but one I use nonetheless.
The value list seemed to work a little easier for the things I use it for.
I suggest a test.
Make a copy of your file and set up a table with the needed values.
Clear the custom values from your value list and then save your value list. Then re-open and use the use values from a field option to refer to the table.
Use save a copy as to save compressed copies of both copies of your file. Note the difference in file size. Then keep in mind that, as far as I know, the difference in size between the two files due to the two value list options should not change as the number of records increases.
I didn't notice a big difference, but in hindsite, there are several spots where I use a value list based off of a table anyway...so not sure I can get around it.
Worse case, I can always archive older years if it gets too big. I rarely need to go back more than 3-4 years anyway.
Thanks again for all the help.