Don't know then. Server+Terminals is historically UNIX networking model, when HDD was expensive. Nowadays HDD's are cheaper but still cost money, plus they are most unreliable part of the computer. With LTSP you can have real heavy-duty server, h/w RAID plus good backup solution, ensuring your data is safe. And it won't cost a fortune. Old cheap P2 and P3 computers serve well as terminals. Overall cost is lower than in Windows-type network, reliability is at least a magnitude higher.
But you say your hardware is incompatible ... multiple NIC's ? Why?
Sorry, can't help, wish you good luck.