Good way/Bad way into Fall Creek Falls SP in TN

Your going to have a climb to get to Fall Creek Falls, it's on the plateau and it’s up hill to get there. From upper East TN and you don't want steep winding roads, I would go west on I-40 to Cookeville TN. And take TN-111 south. Then onto TN-284. Your going to have a pull up TN-111, but it's not crooked or narrow. TN-30 is crooked and narrow, as is the road into the park from the north side.

I have friends who used to live in Whitwell (Sequatchie Valley) the route they used was hwy 28 to Hwy 8/111 (you would be turning to the west) then east on 284. There are signs. To get to the south end of Sequatchie Valley you want I-24 Exit 155 Jasper. To get to there, it sounds like you need to avoid Monteagle Mountain (steep between Kimball/S. Pitts and Monteagle) on I-24. You will have to deal with the traffic thru Chatt on I-75. Veer to the right at the I-75/I-24 split.

As for Hiawassee... take I-75 south. Get off at the Rocky Face exit 333 and head east. That puts ypu on the Dalton bypass. Go east at hwy 76 intersection (ride left lane... they are used to that due to carpet mill trucks) to Chattsworth. Turn south at the intersection to stay on 76. Turn left then right at the traffic light in Ramhurst. Under the trestle, look for the beefalo in the field on the east side of the road (they used to have several there). Turn left at the next road to stay on hwy 76. After that it's a few mildly steep inclines with passing lanes and you drive straight thru Ellijay.... ie: straight thru the first light you come to, vear to the left, across the tracks and (the tricky part) you will need to turn right into a left turn lane for immediate left to stay on 76. That means you will probably block traffic to make the turn. The route is used heavily by commercial trucks. Locals are used to the lanes being blocked and deal with it. Occasionally you have someone beep at you but the light changes quickly. From there it's a long ride on 4 lane divided highway to Hiawassee. Keep on heading east and you eventually end up in Clayton at hwy 441.

Coming from East TN. I-40 west to exit 322(Peavine Rd) to Crossville, TN. I believe 101 will take you to 30 and into the Park.
Just don't take US 127 thru Sequatchie Valley. 30 out of the valley near Pikeville is a hard pull to get on top of the plateau.