Forms authentication provider and federated authentication provider on the same zone - login page question

In a claims based web application I have an Internet zone define that has the following authentication providers defined (within the same zone):

1. Forms Based Authentication with the ASP.NET Membership provider name set to "ADMember" - this is the standard forms based authentication where the user users username/password to authenticate against our Active Directory

2. Trusted Identity Provider with the name set to "SAML Provider" - this is a federated authentication provider where we defined a relying party trust between Sharepoint and ADFS and in ADFS also defined a Claims Provider Trust with an external Identity Provider

I have a question regarding the login page.  When I go to edit this zone in Central Admin we have "Custom Sign In Page" checked and the value is set to:

~/_layouts/customloginpage/login.aspx

However, when I had to run the powershell commands to set up the federated authentication provider (#2 above) I also ran the following command:

$signInURL = "https://<adfs server name>/adfs/ls"

So now, when I try to access the site, it redirects me to https://<adfs server name>/adfs/ls.  This would be correct if I only had the ADFS authentication provider configured.  However, I also have that forms authentication provider configured.  Usually, when there are two authentication providers configured for the same zone (e.g. Windows and Forms) then when you access the site, you get the page with the drop down list where the user selects the authentication provider.  How do I make this happen?  Actually, since that default login page with the drop down list of authentication providers is not very pretty, we would like to have a custom login page, where (maybe) we would have two separate buttons: if the user clicks one of them they will log in using forms authentication and when they click the second one they will log in with that federated authentication provider.  How do I accomplish that?

thanks,