|In your original post you showed:|
Firewall ----> L3 switch (core)----> L2 switch (access)
and I said yes, this will work. You're asking the same question again......lol
I'm not sure why you would need L3 switches on the edge. If you do all your routing in the core (L3) switches, then it's not required at the edge.
We have dual redundant core switches and those do all routing for internal client VLAN's. We have BSD based boxes that are firewall/routers and they do routing for DMZ and server subnets and also between physical locations. While our edge switches are L3, we do no routing on them and could have used L2 switches instead.
Knowing nothing about the network you're designing (some info in that regard would have been handy) I can tell you if you plan to include VoIP in the future, you might want to look at PoE switches on the edge.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.