You can use your own request/response class. You can write it as:
package MyApp::Web::Request;
use parent qw/Amon2::Web::Request/;
package MyApp::Web::Response;
use parent qw/Amon2::Web::Response/;
And use it by web context:
package MyApp::Web;
use parent qw/MyApp Amon2/;
use MyApp::Web::Request;
use MyApp::Web::Response;
sub create_request { MyApp::Web::Request->new($_[1]) }
sub create_response { shift; MyApp::Web::Response->new(@_) }