I installed Hearthfire just last week. I bought Breezehome and installed the BreezehomeTNF mod (goatk's original one - Elianora's Flavor and Shezrie's Breezehome, while great mods, were a bit too fancy for an adventurer still learning the ropes, in my opinion.)
Yesterday I stumbled back into Morthal and found out that Jarl Idgrod had assigned Valdimar to be my housecarl. I bought Windstad manor with the intention of turning it into more of a hunting lodge/outpost - Breezehome will be where my character's spouse and kids live - there are still to many monsters out there in the swamp for me to feel okay about leaving them out there. I stepped outside my front door at Windstad Manor to see a dead Draugr right in the front walkway, LOL! I was amused to see some Horkers nearby - will they go aggro on me if I try to give them a bucket?
What happens to Lydia if I make Valdimar my Steward? I haven't married her or even asked her to follow me. She just hangs out at Breezehome and watches Lucia while I am away. I asked him to be my steward and saw a message flash across the screen that my other follower left, so I reloaded quickly. Can you have multiple housecarls/stewards at different houses?
I think that buying all the land/houses with Hearthfire makes sense. Being a landowner was a really big deal during the Middle Ages/Dark Ages, and it makes sense that it would be in a setting like the Elder Scrolls games. Roleplaying, immersion, and all that. A landowner who is a is a thane in more than one hold would quickly be seen as a powerful person to be reckoned with, whether or not they could also shout their enemies off of a cliff face. >