While Epoxy is the adhesive of choice, try low temp glue gun for minor repairs.  Just use either hot glue or epoxy sparingly to keep added weight to a minimum.
 

Route receiver antenna away from wiring, motor and batteries by placing it out to one of the wing tips or up to the tip of the rudder.
 

Make sure all of the control surfaces (ailerons and elevators) are firmly attached to the wings and tail with the flexible hinge material to prevent in flight mishaps. A spool of 3M strapping tape is a great addition to your field tool kit. Do preflight check after every landing and before each take-off!
 

Never, EVER charge LiPo batteries while they are in the Aircraft!  Remove them before charging.  Use only the proper charger for the battery pack you need to charge.  Using the wrong charger WILL cause over charging and WILL cause a fire.  LiPo batteries ARE a fire hazard.
 

When charging LiPo batteries, always charge them under supervision. NEVER, EVER put them on the charger and leave the charging battery unattended; even for a few moments.
 

Try using a small Pyrex bowl with a Pyrex cover; put charging battery in the covered dish while charging.  Place in an area that while it can be supervised, is not near anything that can catch fire from a battery that has ignited.
 

Woodland Scenics (found at local hobby shop) makes a great foam putty.  When dry it sands perfectly and is as light or lighter then the foam plastic used on these aircraft. This foam putty is great for filling in dents and for minor cosmetic repairs.
 

It may sound basic, however: when hand launching one of these aircraft make sure to hold WAY over your head and not at shoulder level.  Until one hits your head  with it's wing and then cartwheels in mid air before in plunks to the ground will you understand the wisdom of my suggestion!