Regarding the lights, you can get uprated Bulbs (same wattage but better light output) that give a small improvement, but does the Dip light stay on when main beam is on? (some don't), if not this is an easy mod that makes a big difference. HID kits are available and some on here have done this mod, I've considered it but not done it yet as I'm trying not to spend too much on the bike (saving up for new wheels
) and I don't ride much at night anyway.
Regarding the rear lights, the group buy looks like an excellent product but it is expensive, I got an LED board off ebay which, whilst not being as good as the group buy one, is still much better than stock and much more affordable, the seller I got it from still has them listed;
This works well and I don't think it's worth making your own (one-off) at that price.
Regarding the maintenance, don't neglect the belt change and valve adjustments, the results of leaving these can be very costly - some on here do their own valve adjustments but it is quite complicated and many (me included) leave it to an expert.
BTW you can download manuals for a 748 (user & service) from;
Although I'm not sure for which year model but I don't think the 748 changed much, except maybe for the upgrade of the charging system on later bikes.