Whatever you're passionate about! Though if you're looking for short and sweet you may try things with many different approaches to modeling like complex shapes for example soccer balls and tires.
Looking at the example in the .obj it seems like you can just select the cylinder faces, extract them (leaving the original geometry intact and creating a new object) and then push the polygon normal outward.
I agree do whatever is easiest to work with. Your bottom example would be a pain for me to work with because I like loops and rings. Also... Quad Cap? http://www.mariussilaghi.com/qcap.htm
This didn't get much attention, thought I'd bump it just in case. TL;DR; Is there a way to export Blinn-Phong (as opposed to GGX) PBR textures with SPainter (that look accurate in Sketchfab for example)?
Here is a super quick example. Sorry about the bad quality, I am not at my computer and had to try and use MS paint. Hopefully you can see what I mean.
A specific goal for a specific reason is much better than "I want job." For example: I'm learning Houdini because it will allow me to create technically complex assets that I can sell for $$$.
lots of buildings are made this way. There's quite a few buildings like this in the gears of war series. And there's some cliffs made like this. for example http://udn.epicgames.com/Three/ProceduralBuildingsTutorial.html http://udn.epicgames.com/Three/ProceduralBuildings.html
Do you have any reference images you're working from? The legs seems short, but this depends on the chair style. A shaded wireframe would help people to critique your modeling. For example.
I would imagine that it is merged from 2 cameras in one scene - theres a lot of documentation about this online, have a look at 3d games like the little big planet demo for example.
Thanks for the kinds words you guys!! James: Generally yeah Sculpt -> Retopo. For some pieces I build them in 3dsmax and fire them through to zbrush - like the belt buckle for example.