it really depends on the level of depth you want in terms of immersion. Chesko's Frostfall is the ultimate (and perhaps best) environmental mod that affected the PC needs to date. But to get the ultimate experience, you'd need to combine this with other Primary needs mods. I used Frostfall along with IMCN, Battle Field and Injuries, First Aid, Private Needs, Wet & Cold, Showers of Skyrim/Northern Bathouses, Art of the Catch, Fishing in Skyrim, Hunterborn, Animallica, and RWS. Also added some drug mods like Cannabis and SkyHighrim for interesting interactions with NPCs around Skyrim. And some 33% of my 254 mod deck were dedicated to custom foods which was a nice improvement on the vanilla offering. There wasn't anything that crawled, flew, swam, grew, walked or ran in Skryim which my PC couldn't eat, extract alchemy ingredients for food recipes, craft into hygenic aids like soap/shampoo, or brew into some exotic liquor for further consumption. This level of detail made the game WAY more interesting to play. For all the strategic and tactical reasons.
- IMCN -- basically gave PC a digestive system and made my Dovahkin exactly what he ate. The more healthier food like venison, cheese, bread, fish, game etc. he consumed, the healthier he was. The healthier he was, the faster he healed and recovered from his battle wounds. So basically, identifying and eating foods my PC encountered around Skyrim became a mini game of sorts. Besides this, Frostfall's survival skill was designed to improve the PC's exposure to cold and the environment from eating nutritional foods. So Frostfall encouraged my PC to cook more complex foods, stews, porridges, pastries etc. to increase his survivalist rating in Frostfall. So basically, ALL food my PC consumed in Skyrim became a strategic mini game. After travelling over 8hrs or more (on foot or horseback typically with occasional carriage travel), I'd make him break camp. Then go foraging for wood for his campfire. Then hunting or fishing for his supper. He's also set traps to catch a rabbit or two the next morning breakfast. All of this took up some 2-3 hrs, so it was typically twilight when he finally got this ritual done. Then he had to setup his tent, do #1 or #2 if necessary, and go to bed. And that's with him having to tactically deal with enemy NPCs and critters he's encounter while setting up his campsite. Also, he wasn't always lucky at catching game or fishing either (thanks to Chesko's Art of the Catch mod). So there were many nights he went hungry. Or wet and cold because he failed to forage firewood while in the colder holds like Winterhold. So foraging for food and travelling went hand in hand on a daily basis. Frostfall, IMCN, RWS and Hunterborn made the constant search for food a necessity. Because food was either nutritious (ideal case), snacks/junk food which satisfied hunger in a pinch, stimulants (as in alchemy potions), hallucinogens (as in custom drug mods like Cannabis and SkyHighrim), depressants (as in vanilla/custom mod made alcohol . Since food had weight, certain foods needed to be strategically crafted (like jerky, some stews, boiled eggs etc) and carried in the inventory. So my PC could eat it later before or after battle to help with healing. With the exception of food/snacks, all the other consumables could lead to over intoxication and death in extreme cases of consuming too much). Also had a nice custom quest which gave PC ability to craft a special item. When placed in inventory or any container, this item would permanently stop food spoilage in that container. Very useful to have around my HF homes and other custom mansions.
- Private Needs (let my Dovahkin have bowels which in turn allowed him to be constipated, have diarreah, urinate on a frequent basis. This made his traveling around Skyrim (and other custom worlds like Faalskaar) very strategic. If he got constipated while on the road, he'd have to scavenge for alchemy supplies to make a laxative for when he broke camp later that evening. But the right herbal plants weren't always around. So unless he lucked out and ran across an Inn/town/village on the way and/or found a hunter/shopkeeper/inn keeper who sold the laxative ingredients, then he was out of luck. Regular bowel movements meant my PC had to strategically decide where he broke camp. Discovered the hard way that being caught in a blizzard while constipated and doing #2 could have deadly consequences. lol. Also if my PC failed to take care of #1 or #2 before going to bed, he'd likely end up having an accident when he woke up the next morning. Which might require him to bathe if he were say---going to Solitude to pay Elsif a visit. Or just being around ppl in general. Nice thing about the PN mod is that it was compatible with Showers of Skyrim and Northern Bathhouses of Skyrim mods. So my PC could frequent baths anywhere. From his private bathhouse in a custom home, to any of the main hold baths and shower rooms, to bathing in wilderness like in rivers, ocean etc. Even in dungeons if the water was deep enough. The cleaner he was, the less likely his wounds became, and the faster he could heal based on the Battle Field and Injuries mod
- First Aid and Battle Field & Injuries Both these mods basically gave my PC injuries on places of the body where he was attacked. It also tracked all these injuries/wounds sustained while adventuring on the road. PC could craft bandages and disinfect bandages (based on alcohol and other potions) to treat these wounds. If the more serious wounds weren't treated with bandages, potions, bathing and disinfection, the minor wounds could become infected. This would affect the PC's combat skills and appetite. And the lack of good nutrition would harm the health stat even more. Also for the more grave/serious injuries, if the PC failed to seek the help of a professional healer over a while time, the wounds could end up killing them from the infection. Their combat and other vital skills like archery necessary to hunt for food, or fish etc. would be impacted. So the PC's overall survival skill set would be negatively impacted
IMCN has to be the best primary needs mod even though RND was the most popular Skyrim needs mod to date. Unlike RWD, IMCN was far more complex in the stats it tracks. It monitors not just what your PC eats, but how well your PC's food nourishes them. And IMCN recognized a wide variety of custom foods (Babbette's Feast, Fishing in Skyrim, Wolferoo's 80+ recipes, Hunterborn/RWS recipies etc etc.) It also limited your food intake, and adjusted the PC body fat v. muscle makeup. Private Needs was a nice compliment because by adding PC bowels, it basically justifed all the food intake my PC constantly gobbled on a daily basis.
Well enough babble. If you didn't last this long, then TL;DR
hardcoe mode with eating/sleeping/thirst/hygeine/injuries tracking/regular bowel movements, and some sort of environmental effect on PC health features are the only immersive way to do FO4 IMO. Because that is about the only way you'll avoid ending up being "bored" and "just hitting a button to refill the bar". In which case, hardcoe mode would be completely unnecessary, since you're likely playing with tgm or some other inventory weightless/god mode health cheat on.