Yeah, special characters are always made outside of the normal balancing rules.
These rules basically work like:
statistics + usefulness (within context of other units in army)+ special rules = points cost. Basically.
Special characters --
are either a) are too cheap for what they do
or b) are too expensive for what they do (much, much more common, actually)
or c) change the way your army is composed (like making special units core choices). This can lead to some utterly ridiculous armies if taken to extremes, which people always try to do if you let them (especially when there is competition and prizes on the line ;p).
It does kinda suck, but just wait until someone fields a special character against you in an actual competitive event that changes your win to a loss by simple dint of it being there. Its better, overall.
Please note, according to the rules, all units are armed with the same stuff (subject to change only in the rarest of cases, requires special rules). You can't have some saurus with spears and some with hand weapons in the same unit, the whole unit has to be armed with either. However, saurus with spears still have hand weapons, you can the one point for spears means that you can choose to use either, depending on whethere you want more attacks or armor save.
In terms of modelling, you need over half representing the weapons that you bought for them.
Re-post if I misunderstood what you meant or if I wasn't clear enough.
The engine of the gods provides magic protection and a magic phase for your cute little priest on top.
Most big lizardmen armies have at least one, because they are really good.
