Raleigh Sports Model DL-22 frames break. All of them. If yours hasn't broken yet you just don't ride enough. Frames from an earlier era have a decent chance of some longevity but still fail. 1973 frames break fairly quickly. Adding a motor will accelerate failure. Worst possible choice for an already dubious project.
I did not bother to bookmark the source but it was on first page of a simple google search on e-bike safety. You can find it if you care. In Netherlands, where e-bikes are very popular 90% of accidents, injuries, fatalities happen to riders over 60 years of age. Sounds like the C&V demographic. Yes, fatalities, and enough to build stats.
My opinion is soured by the fact that I have recently been hit twice by e-bikes. There are not that many of them around here. My winter miles are nothing like what they used to be. Until 5 or 6 years ago being hit by other cyclists was not even a thought. Now it happens and e-bikes are the worst.