I will say the 4runner isn't for everybody. Sounds like you may have some engine issues which are pretty rare, my 5th gen's engine is pretty quiet but my 4th gen's engine does tick quite a bit. Nothing to be concerned over, that's just how they sound. My 4runners won't win any drag races either but I feel they get me down the road ok. I didn't care for the stock suspension/tires either but I knew that I was going to replace all that anyway (Icons, SAW rear springs, BFGs) and now it is the way they all should come. I will agree about the Entune Navi, the few times I've used it, cumbersome and it seems to take you all over just to get from point a to b.
I can't really comment on the 2015 ecoboost but I did have a 2012, complete with the 36 gallon fuel tank. I really liked it at first but by 40k it was having a ton of issues that FoMoCo either didn't know how or didn't care to fix. I only had it tell me I had an 800 mile range once. At 42k that range was down to 400, the crankcase would fill with gas, the intercooler would fill with oil, knocked like an old cold diesel on startup, and I'm pretty sure my 4th gen could've beat it in a drag race. Plus the electronics inside would go haywire or not work at all. Yeah, I probably just got " a bad one" but my last two fords have been that way. Hopefully you won't have to experience any of that. Me and the Ford garage were on a first name basis with each other. I just got tired of driving something like that. I traded it for my 5th gen.