
Congratulations on your puppy Nigel!
Borders thrive on human attention, and at this very tender age you can teach and learn a lot. You seem to have most things covered and have obviously done your homework, so well done!
About "placid" Borders, I have known a few laid back ones, but I would think Jasper is just settling in at the moment, stand back and wait for the rush when he feels confident enough. My Borders are very "buzzy" little dogs, but very controllable, get those commands into Jasper now and you will be fine. One thing I always do, is as soon as the pup can go out, loose him with a well behaved dog and its the ideal time to get him to come back, reward him with a treat, he will still be insecure and won't venture far, and will stick with the other dog, so training is MUCH easier than with a confident half-grown yob!
Good luck.
Dawn.