[HELP] Recommend for this topology ( optimize local network )

[buivietha]

hi everyone,
i have this network topology ( picture attached )
Prepare for this object i use Pfsense version latest ( example: Pfsense 2.2 RC - release 01/12/2014 live CD install ) run on hardward ( server IBM IBM System x3550 M4 - 1CPU E5-2650 with 4 NIC 1000 Gib )
for purpose : 3 wan PPPoE to 3 ISP, routing Vlans, monitoring ( snort, squid, squidguard ) and firewall between them

Switch Cisco layer 2 ( create VLAN ) connection to normal switch in each VLAN ( saving port on switch Cisco)

The network has about 1000+ pc and server VPN IPsec connections.

Can anyone help or suggest me best solution for that ??

Thank you so much for spending spare time to read this topic

email: hascar87@gmail.com
skype: buivietha6187