upgrading stuff won’t make you better …. or quicker…. (really by much)…. so just spend it on fuel taking you to places where you can ride more
This is very good advice.
Personaly the wheels don’t sound too bad, not to say that an upgrade to Hope/Stans wouldn’t improve them, but I personaly found alex rims to be as good as anything else (and converted to tubeless really easily with some electrical tape and an old valve).
Looking at that spec the only thing that jumps out would be the fork. I’d save up for a SID or Reba, or speek to LOCO and see if the internals can’t be upgraded if the rest of it’s good (unlikley to be economic though, probably £250 on dampers and a £100 service, Vs selling them for about £80 and just buying new forks.
I presume you’ve swapped to SPD’s, if not, do it!
Stem and post might drop a smidge of weight and look bling, but won’t affect the ride too much.
Bars might drop 100g and be more comfortable, but are the old ones uncomfortable?
Drivetrain – wear it out and replace with SLX or XT and save a lot of weight.
Brakes – they’ll be fine, no point upgrading
Tyres – if worn, replace with whatever’s the best and most suitable, and tubeless! This would be my #1 thing to do.
Saddle – is it comfortable?
Basicaly, just run it into the ground over a few years, replace bits as they wear, a new fork and wheels with convertible hubs will be a good investment if you ever upgrade the frame to a full suspension frame (as long as it’s another ~100mm 29er). Spend the spare cash on nice shorts, jersey, shoes, helmets, gloves, grips, glasses, a really good breathable waterproof, chinese lights, etc, that stuff really makes a difference to whether you enjoy a ride or not, a 100g lighter seatpost won’t, but will cost more than a nice pair of bib shorts, and a better wheelset will make you a smidgen faster and the bike feel nicer, but will cost 2x more than even a very nice rain jacket, and a £250 jacket will let you ride all year round in comfort, rather than shivering/sweating but being on lighter wheels.