From what I can find the weight difference is only 600g, would that really make much difference when we’re talking about 12-13kg bikes?
I can be pretty stubborn so will probably end up relearning without and suspension. I’m 99% sure most my rides would end up being solo yarra trails so chasing suspension riding folks isn’t a huge issue.
Now to play the waiting game. Hoping a cheap Unit comes up on gumtree or mayeb even one of those steel Haro 29ers.
A Kona Unit frame with a carbon fork some decent wheels and parts should be around 10 - 10.5kg. The crave from memory is only about 11kg as stock. I could be wrong tho.
Before I bought my Salsa El Mar, I looked at the Unit until I picked it up (they are really porky). Also the P2 fork is not gonna ride nearly as nice as either a full carbon fork (like my cheap chinese jobbie - XMIPlay) or a susser.
Or another one you could look out for is a Surly Karate Monkey.
Anyways.
If steel is your thing have a looksy at Singular as well.
I recently picked up a unit, which I’m running with a 100mm fork. Having previously owned a Trek Fuel I don’t particularly notice the weight of the frame. I rode it for a while rigid, t’was fun around yarra trails but pretty limiting on anything else (possibly due to my “direct” riding style). With the sus fork, I’m happy on everything but the DH tracks at the you yangs - it’s perfect out at wombat.
It’s a little longer wheelbase than an XC race bike, and a couple of KGs more, but it’s a fun bike to ride, and you can always put gears on it if you want.
Stock parts a bit heavy but not likely to fall apart. The rims are reasonably wide with tubeless with tape from the factory, and you should be able to set up the tyres without too much trouble. My only issues have been that the bars had too much rise and the headset is not sealed cartridge bearings.
It’s a fun hardtail really, and pretty cheap compared to trek and specialized alloy options.
Hearing good things about the Unit definitely has me leaning towards it. Also found a pretty cheap Redline monocog which seems to be quite similar to the Unit. Thinking about buying it but can’t seem to fine any decent/credible reviews online.
Unit, 2012 or later. The 2016 one is the tits! But others also great. Redline, never heard of someone really falling in love with one, but the unit has fans all over the place. Dan mustve picked one up complete with saddle bag containing ten tubes. Reynolds 520 isnt superlight, but it surely shits on whatever the karate monkey is made of, in terms of weight anyway.
This is one of the coolest bikes I own 
There was a monocog setup as a rigid SS for sale near me a while ago. I almost bought it. I think the only downside was that it’s heavy, and a little bit ugly.
Pretty solid bike though. Down the track you could chuck on some short travel forks if you really wanted.
The geo on the 2016 unit looks really good.
69 headangle and 434 CS will be fun, I’m on similar (69.5 and 435) on my awaba and love it.
More useful information, this thing climbs like a beast. Better than I can push it.
Comes standard with Stans Rapids which seem to be between Crest and Arch EX (OEM only rim).
The rocker (alternator) dropout means you can run a single speed rear with a QR which is really nice and is really simple to change a flat without having to dick about with chain tension & rotor alignment.
Longer fork that previous El Mariarchias (483mm vs 468mm) & 44mm headtube so will take a 100mm fork with a tapered steerer.
The steel fork rides quite well and I haven’t felt the need to change it yet. Has 15mm thru axle so it’s easy to swap for a sus fork.
The new model is basically the same except colour as this model isn’t available anymore, you might find a store with one in stock if you’re lucky and want this paint scheme.
I looked at a Kona Unit, Surly Karate Monkey, Niner S.I.R & Singular Swift.
This just seemed to tick more boxes and I was lucky enough to find one locally.
EDIT: The only mods I’ve made is a red chainring, coz red, swapped tyres to Crossmarks and setup tubeless (it was summer when I bought it) and swapped grips to ESI.