There seem to be some issues in your parsing of numbers. It appears your logic to determine types fails particularly on bytes. You may want to take a look at the spec for abstract types at http://www.odata.org/documentation/overview/#AbstractTypeSystem. You will probably have to reorder your logic for detection.

For example. $filter=Field1 eq 9999 captures 999 as a byte when its not. The format for bytes is 2 characters [A-Fa-f0-9]+ so this results in a failure for the call.