Assuming you like ground glass viewing, as well as inexpensive, try a Japanese TLR like a Yashica Mat, Autocord or Diacord. They have fairly bright viewing screens and decent Tessar-type lenses. Personally, I don't see what the big deal is about strictly mechanical cameras though. An SLR with an electronically-controlled shutter, like a Bronica ETRS or SQ series will have accurate shutter speeds, and the battery lasts and lasts (if you are not using a metering prism). You can carry a spare silver oxide battery in a little pocket of your bag if you are concerned and you are good for years. My ETRSi seems to work fine even in freezing conditions. An SQ or ETRS with normal lens and WLF is about the same size and weight as a TLR and somewhere in price between a Rolleicord and a lower end Rolleiflex. The main thing to keep it light and compact is to use the WLF and not a prism or speed grip.