As a person doing business on the internet, I have tried almost all of the freeware alternative msn client. Miranda is not bad but not as good as trillian (at least for me). It has a lot less features than trillian and GUI is less intuitive. Having less feature means less bloated as well but doesn't mean better. There should be balance between usability and resource hogging. Also, miranda is not as stable as trillian. I find miranda get disconnected now and then with MSN. But I only used it for a while as I did not like it. Maybe it's the interface or maybe it's the features or combination but it was quite some time ago.

BTW, trillian also is able to save chat history. No need add on.