I may not be the best judge since HG is the only game I've Nuzlocked but I didn't find it that bad. Most of my deaths have been from overconfidence or bad luck, and it's not too hard to build a balanced team if you have no repeats. While the first 4 Gyms can be difficult (Bugsy not really unless you didn't start with Cyndaquil and have horrible luck with getting Geodude) they're all doable with fairly common Pokemon (Falkner with Geodude and Mareep, plus Totodile and Cyndaquil can usually power through him if you're careful, Whitney can't touch Geodude, and any normal type with a move good against his ghosts will laugh in Morty's face), and once you get past that it's pretty well easy street until Clair.
That being said, be prepared to grind; one of the biggest things that pisses me off about HG/SS is that they didn't fix the levels, with Pryce being roughly equal to Jasmine (probably because you can do Mahogany Town before heading to the west side, but still), then Clair jumping up a good 6 levels with virtually nothing in between her and Pryce. Then a similar jump from Clair to E4 with similar circumstances, then you breeze through Kanto only to find yourself level 60ish at most with Red in the 80s and the E4 in the high-60s and Lance in the 70s. The only thing they fixed was boosting the Kanto Gym Leaders above Lance (in some cases only just barely), and even then a lot of random trainers are not only below the E4 but just way too low in general (for example, I'd say about half the trainers on the route between Lavender and Fuschia have Pokemon in the 20s when you're in the 50s -_-). Either grinding or very patient abuse of the time system to get rematches with Trainers (and later on Gym Leaders) WILL be necessary for a successful run, count on it.
As for my own challenge, still grinding -_- The only problem with the Gym Leader rematches is that I generally only play on the bus to and from university, so I have no idea what are the times for rematches. One of these days I'll write them all down so I can abuse the system and train quicker but until then gogo snail pace -_-
That being said, be prepared to grind; one of the biggest things that pisses me off about HG/SS is that they didn't fix the levels, with Pryce being roughly equal to Jasmine (probably because you can do Mahogany Town before heading to the west side, but still), then Clair jumping up a good 6 levels with virtually nothing in between her and Pryce. Then a similar jump from Clair to E4 with similar circumstances, then you breeze through Kanto only to find yourself level 60ish at most with Red in the 80s and the E4 in the high-60s and Lance in the 70s. The only thing they fixed was boosting the Kanto Gym Leaders above Lance (in some cases only just barely), and even then a lot of random trainers are not only below the E4 but just way too low in general (for example, I'd say about half the trainers on the route between Lavender and Fuschia have Pokemon in the 20s when you're in the 50s -_-). Either grinding or very patient abuse of the time system to get rematches with Trainers (and later on Gym Leaders) WILL be necessary for a successful run, count on it.
As for my own challenge, still grinding -_- The only problem with the Gym Leader rematches is that I generally only play on the bus to and from university, so I have no idea what are the times for rematches. One of these days I'll write them all down so I can abuse the system and train quicker but until then gogo snail pace -_-