We would love to make the ribbon a simple loop, this would solve a lot of problems, unfortunately the ribbon would break.

As for boosters the fuel for them would cause a very large increase in the climbers weight.  The rockets used by NASA are practically all fuel tank.  The large rockets are needed to move a capsule the size of a small truck 100 miles, on the flat road vehicles use a much smaller fuel tank.  Although a lot of the fuel is used to accelerate the capsule to 27,000 km/h.

The strength of materials is called the tensile strength and is measured in pascals.  Steel has a tensile strength of 2,000,000,000 Pa (or 2000 MPa) and carbon nanotubes 62,000,000,000 (or 62000 MPa).  The space elevator cable hangs down so a measure called the breaking length is important.  This is the length of material (in km) that can support its own weight.  The breaking length of steel is 25.93 km and the breaking length of carbon nanotubes is 4,716 km.  Pity the space elevator will be 100,000 km high.

http://en.wikipedia.org/wiki/Specific_strength

Using a doubled back cable that rocks up and down to lift the cabin instead of an on board motor has been proposed, avoiding the heat problems, but this is just a dream until a super strength material has been invented.

Weaving does have some advantages, but it does not increase the strength per kilogram. Long runs between high tension towers are typically solid copper wire. Search for Hoytether which is something like a fishnet.
The rocking back and forth method does allow using tapered ribbon, and suitable CNT = carbon nano tubes may be available soon. There may, however, be some surprises when we try to do the rocking method very large scale. There seems to be some disagreement about the behavior of stretch transients, and the degree of dampening = energy loss which will occur.
Ribbon heating may not be a problem as CNT can tolerate very high temperatures. Hot ribbon will cool efficiently by radiation. Epoxy or other binders will deteriorate at a few hundred degrees c. The laser beam used to power the climber may accidentally heat the ribbon and cause heat damage to the binders.   Neil

That's it -- actually, thickest near GEO, and tapering both up and down from there. The taper reflects the fact that each segment has to support the weight (going down) or centrifugal pull (going up/outward) of all the ribbon beyond that segment, as well as the smaller forces imposed by climbers and their movements.

The conveyor belt design of space elevator does solve many problems, unfortunately the ribbon needs to be made from an even stronger material.  One so strong that the ribbon can be made without tapering.  It is unlikely that even CNT will be that extra strong.