This thread has been beaten to death but I figure I'll throw in my 2 cents, since I've owned and used a fair number of them from various brands over the last decade or so since I got into film photography in earnest.
The right answer is, there are probably many, many right answers. I've owned and used the following 35mm cameras, and they all have their pros and cons.
Canon Elan II: Probably my first choice most of the time. I came to film after years of shooting digital. My workhorse DSLR is a 5D Mk II, and the ergonomics and controls of this are a nearly perfect match. I also already have a good collection of excellent EF-mount glass. So while not all of this necessarily generalizes to everyone, this camera is fantastic for me. I love having autofocus. I love having electronically accurate shutter speeds all the way up to 1/4000th in half stops. When I'm shooting 35mm, a lot of the time I'm looking for a faster, less technical approach for the day anyway, and this camera fits that perfectly. Canon EOS bodies in general are criminally undervalued these days. I picked up this Elan II for $30 a few years ago.
Canon Rebel G: I interited one of these about a week ago. It has largely the same advantages that the Elan II does, but it's an obviously lower-tier body. The biggest thing I miss compared to the Elan II is the thumb wheel for aperture control. I'm not going to keep the camera; it's redundant. I will find someone who can give it a good home.
Olympus OM-G: I love it for how compact it is, and the access to excellent and well-priced OM Zuiko lenses. I'm not in love with the shuttter speed controls on a ring around the lens. I know some people love it, but it's not for me. Not a deal breaker though. The Olympus winder is really inexpensive right now, so I have one that basically lives on here. It's not as well-designed as the Canon winders, but it's nice to have. My biggest complaint is that the shutter will fire at something like a fixed 1/60 even if the camera is set to off or the battery is dead. I'd rather it just didn't fire, I have wasted a roll of film shooting at the wrong shutter when I thought it was shooting at the speeds I set on the dial.
Olympus OM-1: Got this at the same time as the Rebel G. This one I'm keeping. All mechanical, battery only needed for the meter. It has a self timer and mirror lockup. It has a ridiculously good viewfinder. Best I've ever looked through with the possible exception of my buddy's Pentax MX. Huge, clear, has a split image prism. Meter needs a 1.35v battery. My current solution is a cheap brass adapter that lets me use a 1.4v, size 675 zinc air hearing aid battery to get accurate meter readings. I may install a resistor in the meter circuitry to allow for a silver oxide 1.5v battery, the zinc airs have stable voltage, but I have to pull them out and expose them to air if they've been in the camera awhile, and they don't have the best lifespan.
Canon AT-1: This camera gets the least use of my 35mm collection now. I may give it away. There's absolutely nothing wrong with it. But I like the AE-1 more in every category.
Canon AE-1: I know it's overpriced due to the cult following, but frankly it's a really great camera. I love using it. I have a Canon winder that sits on it full time. It uses a modern battery. The meter in the viewfinder is very intuitive to me. I also love that it doesn't need to be switched on and off - it's smartly designed so that it's essentially always on, but preserves battery when not truly in use. I know it doesn't have the 'fully mechanical, built like a tank' thing going for it, and I suppose it will eventually die an electronic death. But I love shooting it, and I baby my cameras, so I think it will last for years to come. Canon FD lenses are good of course if you get the good ones, but they're not a particularly great value these days, since they adapt well to a lot of mirrorless cameras and they're a very recognizeable brand name.
Canon FTb QL: I think either this camera or the OM-1 will be the one that outlives me. All mechanical, heavy, indestructible. Battery only needed for the meter. Same issues with battery voltage as the OM-1. This is essentially the equivalent of my OM-1, with a few minor advantages and a few minor disadvantages. Biggest thing this has over the OM-1 is the control scheme. I like having the DoF preview on the same springloaded lever as the timer. I like having a shutter speed dial on top instead of around the lens. I wish this camera could take a winder. I wish I could get a split-image focusing screen for it, I don't like having only the microprisms. It's also not a particularly bright finder. Still, a solid camera that I like to use when I'm taking a more methodical, slow approach but still want to use 35mm film. The quick-load feature is nice, but not really necessary.
Zorki 5C: I hated this camera and gave it away. The film loading was horrible from the bottom. The focusing was difficult and imprecise. The lens was nothing special despite being of the cool retractable variety (I had an Industar-22). The rangefinder was dim. The viewfinder and rangefinder being in separate viewing windows was very inconvenient and frustrating to me. Many of these issues are ones that I can't chalk up to it being a poorly executed copy of a Leica. I don't want the Leica either. I'm just an SLR guy, I suppose.
So there's my unnecessarily detailed review of all the 35mms I have experience with. For what it's worth, I like shooting most any of them (with the obvious exception of the Zorki). I could be fine if any one of my collection was my only 35mm. But I like having the slight differences and subtle advantages of the different cameras for different types of shooting. And if I was coming to the world of 35mm from large format, I think the OM-1 is probably the one of these I'd choose.