40 to 70 degrees c !?!?!?!? isnt that a bit hot
No these are normal basking temperatures found on many surfaces on a hot day. Just make sure the whole enclosure doesnt get too hot, a 50 watt halogen spotlight can easily provide a good basking spot like this without wasting much heat.
I dont think the need as big an enclosure as some say, but more importantly give them lots of branches and pieces of bark and other hides to cruise around and forage in. I have roaches livng with mine to allow them to hunt whenever and also feed them meaty snacks, spiders and other critters occasionally.
They are unlikely to bite as mentioned, but if they do bite they are unlikely to cause any blood or pain.
are there any monitors that are a bit bigger than ackies?
for some reason in the monitor family the just seem to jump from XS to L, were's the medium? i find that ackies are a little small anyone else have any suggestions?
Sand monitors are very medium sized, but big enough to give a reasonable bite. This link has basic info on most monitor species, it does include exotic spcies too though.
Mampam Conservation - Species List