I say give warriors a load out option. keep them at 1 wound, keep them at horde bonuses (maybe switch the 20 with the 30) keep them at 5+ save. but make our weapon choices matter more than just range. allow them to mix and match weapons like the skinks can. you could even keep the stat line foe the weapons the same, just allow for each individual weapon to be an attack (example two clubs, 1 attack with each, club and spear, 1 attack with each). equipped with: two clubs? +1 to wound. spear and club? both weapons count as having 2" range (fluff you stab them with a barbed spear and kind of pull them into range of the club) weapon and shield? save goes to 4+. two spears? too unwieldy and not allowed. remove the shield from the Jaws stat line description, so you always have the jaws attack no matter your load out.
this would give us options, make us either slightly more durable or slightly more aggressive (at the players discretion not GW's!). (4+ save is better than ignore 1 rend all day every day)
meh, that wouldn't do much to solve the issues they're facing.
They'd still be rather squishy unless you take the shield
They'd still lack offense if they take the shield
They'd still be useless at minimum size.
They'd still be far to expensive to field more than 1, maybe 2 "usefull" units at max size.
Also, in this particular case the amount of combinations and effects might make things a tad complex. Skinks work because the various options don't interact. Having the weapons interact in different ways depending on the loadout might end up being too complicated to balance.
Though that does give me a halfway decent idea. Why not just make spear & club saurus effectivly 2 different units.
Give spears a 3" range, making them the preferred option for hordes as the 2nd and 3th line are near guaranteed to be able to reach their target as well. The fluff being that equiped with spears they fight in a very organized phalanx, the backlines supporting the frontlines. Hell, give us new models with proper sarissa's to make it nicely visible.
With clubs they get 2 bite attacks, and the clubs get -1 rend. Making them worthwhile in minimum sized units. The fluff explenation being sauri with club can fight much more viciously taking greater advantage of their primal nature and superiour strength with clubs while spears require them to form up neatly and fight in a more orderly fashion.
This way you have seperate setups for both minimum sized sauri as well as large hordes. The options are also different enough in terms of strengths that they shouldn't really see use in the "wrong" case making it relativly easy to balance. Plus it feels appropriate fluff wise.