You could potentially configure a monitor with the request being made to a status page. The receive string would check for one particular node IP and its status. The downside is that you'd need to configure one monitor per pool member and assign a member-specific monitor to every pool member individually. I'm guessing it would be easier to use your existing method.
The monitor configuration would look something like this:
monitor http_alias_monitor {
defaults from http
dest 1.1.1.1:http
recv "10.0.0.1 UP"
send "GET /status_page.php"
}
The dest is the IP:port for the server which hosts the status page. The send field is the request LTM would send. The recv field is what LTM would expect to get back in the response for that request. 10.0.0.10 would be the IP address listed in the page content of the status page.
Aaron