For just a private internal network, it would hardly notice the extra load.
I assume you won't have thousands of machines coming in and out
regularly, but only a few dozen at the most coming in a few times
per day. No problem.
Some of our sites have several hundred machines using DHCP, on a machine
with web, DNS, majordomo, squid proxy, squirrel web based Email running.
About the only thing that slows them down is spamassasin/procmail when
lots of Email comes in.