At the risk of being late to the party, I thought I would chime in with some advice. I'm far from 14 (more like 38!) but I only got serious about photography maybe 5 years ago. Enough time to try lots of different cameras and camera styles.
There are two conflicting needs here: a small enough camera to pack in the bottom of a backpack; and a camera that is usable and reliable enough to actually be used on vacation.
I vote against a folder. They are attractively small when folded, but the viewfinders are universally tiny and painful to use for serious photography. Very few folders have a rangefinder. I don't think learning your focussing distances "on the fly" and getting half of your irreplaceable vacation photos out of focus is much fun. And most folders under $100 will need some serious TLC. Camera repair is a different hobby than photography
A TLR might be a better choice, but the OP doesn't seem overly interested.
Based on what the OP said, I recommend one of two cameras -- either a Fuji GW680/690, or a Bronica ETR system.
The Fuji GW cameras give you a nice big rectangular negative. The lens is sharp -- but fixed, so no changing lenses. The viewfinder and the rangefinder patch are HUGE and accurate, much better than you will ever find in a folder or a 35mm rangefinder. These cameras are built like a TANK and will take the abuse of being stuffed in the bottom of a backpack. Film loading and camera handling are much more like a 35mm camera, which will speed your learning curve and encourage you to shoot lots.
In favour of the Bronica, is the small size and different way of working. I think that a waist-level finder is a wonderful tool and great way to slow down and consider composition, focus, etc. A Bronica ETR with waist level finder, 75mm lens, and film back, is one of the most compact, lightweight, easy-handling medium format cameras you will find.
Yes, the 645 negative is smaller. But 645 is a great format for "real world" use. If you want to learn darkroom, it's easier to get a good quality 645 enlarger than a 6x7 or 6x9 enlarger. If you are having your films scanned by the lab at time of processing, the 645 scans very well -- effectively giving you bigger scans than 6x6 which is cropped later.
You can add to the Bronica now or later. In addition to the body, wlf, 75mm and one back, I would get:
- a second film back. This will let you carry two different types of film, loaded and ready to go.
- a metered prism and speed grip. With this combination, the ETR goes from "Hasselblad mini" to "35mm SLR maxi".
- 50mm/2.8 - because it's a much sharper than the 40mm/4 MC, and it's a stop faster
- 150mm/3.5 - because it's about as big a lens as you want to carry in a backpack, and about as long a lens as you can handhold comfortably. It's a fantastic portrait lens.
Of the ETR equipment you already listed, I would avoid the 40mm MC. It's just not a good lens. If you can afford the PE, then sure. But the MC isn't worth the heartbreak. The 250mm MC is a good lens, but 5.6 is slow, and the lens is big and heavy. With the 250mm you are going to definitely want to use a tripod. Unless you need the length and are going to carry the tripod everywhere, don't bother with the 250.
Finally, if there is one place to not skimp on a Bronica ETR, it's the film backs. The backs are the one thing that will wear out first. Spring for some nice EX-rated backs instead of the UG or BGN. No need to take a risk to save a couple of bucks.