i only fast travel within whiterun sometimes to go to the castle. i do some heavy RPing though. i change into smithing gear and burden my character so he has to walk around when i am taking a break from adventuring.

I will take a carriage. i only wish there were at least random bandit encounters when taking one, it feels too safe. Rarely i may have fast traveled if i forgot something at my house, and im not too far.
I keep quest markers on though, i see it as just my characters intuition in his environment, and it also represents me constantly checking my map.

It's not hard at all to have your character walk places! I find it relaxing sometimes to just sit back, hit my computer's C key, and drive my character with as little input as driving a car with an automatic transmission ... just point and go. There are times when I wish I could get more done during a gaming session, but it's not like I need to finish by end of the year or anything. So, yeah, most nights all I have to look forward to is making it back to , but nothing matches the satisfaction of getting back "home" after an epic journey!

Are we there yet?
YES!

i like to think i RP. i use fast travel quite a bit. saying that i also walk place to place probably about the same amount. it mostly depends on time. for example weeknights i'll generally fast travel. weekends however i'll generally just walk to where ever i'm heading. i prefer walking place to place for many reasons, random events/encounters, picking herbs etc... the only problem with walking tho is its very time consuming, and i tend to get distracted easily... come here butterfly.. oh [censored] there's more over there....

i've never considered myself as a casual gamer for any game, simply because whatever game i play i usually sink myself deep into it, unless it's not a great game, then i'll move on.
i don't view certain aspects in any game to make it more casual than hardcoe. i view the gamer themselves as casual, for example imo a casual gamer is someone who likes to play games, usually multiple games, but they don't get 'into' the games they play, if you know what i mean?

Same here, started around Level 58, now I am Level 64 100+ hours.

Some hard-core RPers actually do fast-travel a lot, since how they get around often has nothing to do with the character's role.

I'm not as hard-core an RPer as some folks, but I do tend to follow a given role fairly strictly; as such, if the role calls for the character to visit the various Holds' capitals on a regular basis I'm definitely going to be fast-traveling all over the place, whereas if it's a role that requires extensive wilderness travel I will mostly use fast travel to get back to 'civilization' once I can't carry any more stuff. Here's an example:

My current character is a thief, who has two cover identities: blacksmith and veteran mercenary. The former is used to 'launder' stolen goods whenever possible, (i.e. melting down and then reforging rings), while the latter is used to both build up a good reputation with the towns and keep the local toughs from trying anything stupid. As a result, he spends a fair amount of time wandering around clearing barrows/forts/whatever to build up rep, which requires constant traveling between the holds in order to take on more tasks. Once he has a reputation as being both dependable and honorable he starts practicing his true profession, which gives him a lot of items to convert and sell; he cannot risk such sales in the town he got them from, lest they somehow be traced, so he again has to make the rounds in order to dispose of everything. Since he mixes the illicit goods in with his haul from various ruins, nobody gets suspicious when he unloads large quantities of valuable items at once; this allows him to repeat the process when/if needed, as well as making it unlikely that anyone will try to finger him if something particularly precious suddenly disappears.

This character covers both sides, since he is either fast-traveling a lot or not at all, depending on which persona I'm currently playing as. If the mercenary side gets a mission a long distance away, I'll use the carriage to get to the Hold nearest the destination rather than fast-traveling there, and then go on foot the rest of the way.

I don't walk for the sake of walking, since I don't see any point in repeatedly covering an area I've already picked clean, however after clearing a given interior I often immediately head for another one if I still have spare carrying capacity, since I only sell when I can't carry any more. If this happens mid-interior, I'll clear out some more creatures/NPCs and then put on my Fortify Stamina/Increase Carrying Capacity outfit so I can drag out even more stuff. Once that runs out I FT to sell everything, then FT back and continue looting. If I run out between a FT-eligible point and one I'm trying to reach, I FT to a selling point, then back to the point I'd left from and start heading toward the new place again. Sometimes I discover that the first route is not practical, so I try a different path on the second trip; this often ends up with me sidetracked into a completely different location, and having to sell yet again before trying to reach the original destination.