Theres a YouTube channel called experimental airlines, look him up. He covers his entire planes in colored packing tape. Looks good and adds a lot of strength, as well as water proofing and what not. He's got a lot of good informative how to videos. Here's a link on one of his videos showing how to cover foam board with tape.
There are numerable methods espoused on the forum on how to make DTFB planes more durable and the use of tape is but one.
Other methods include the use of sealing and painting, the use of vinyl wraps, Fibre Glassing, Balsa cladding, and the like. There is even someone who espouses the ironing of the FB edges.
Over 3 years ago now I was building Depron models when my supplier discontinued stocking the product so I had a myriad of plans for which I had no ability to build. I searched around for another supplier and found a FB supplier which I still use today. As it looks somewhat similar I tried making Depron models in FB. The FB was not only heavier but was not as rigid and did not handle very well in the long term.
In an attempt to make the FB stronger and more resilient I tried many different coatings and found one which even allowed me to build large single layer FB wings without any spar material. It requires a little patience and practice to get it perfect but I coated the FB in PVA glue. The reason for the patience and practice is that the PVA tends to cause the paper on the coated side to want to shrink which in turn causes the flat FB to "Cup" or curve towards the coated side. By applying the glue ot both sides and using a little water to slow the drying I managed to get the sheets to dry uniformly and perfectly flat, When the wings were cut out and finished I further painted the PVA glue on the FB edges,
When the plane was assembled and the glue was dry it was just a simple matter of spraying on the desired colour from a cheap rattle can of paint.
As for resilience I flew the biplane I have built and coated in PVA hundreds of times and it seemed that it was attracted to trees and fences as all I can remember is getting it out of almost every tree at my flying field and how the plane suffered very little real damage. Sure I had to glue the wings and tail back on at least once a fortnight but the single layer flat FB wing was still rigid and able to support the plane in the air right up to the day I stripped out the electrics and fitted them into my next or replacement design.
Lots of methods around you should scour the forums and much will be revealed.
I kinda look at it a different way to me it is only foamboard, and it will not last like a balsa build. FB planes are cheap and quick to build longevity for me can be short as I beat the cr-p out of them and fly them in smaller areas then I should.