If you have one of the clamp on ammeters you might be able to open up the breaker panel and clamp around the hot legs of the devices while they are running and see what you get.

I just did this a little while ago in reviewing my own needs. 
3KW(sustained load on a 6/1 genset?) is about 12.5 Amps of current at 240 VAC or two 120VAC legs at 12.5A(25A total for both 120volt legs) or some combination of the two.  As an example, my electric oven draws about 10.8A @240VAC on Bake.  The duty cycle will of course drop off dramatically after the oven is up to the set temp, but each time the controller cycles it on, it will pull that much.  That dosn't leave much leftover for any other loads, but it is doable on a 3KW sustained budget.  On my range, a large electric burner on high pulls 8.5A @240VAC. A large and small burner combined pull 14.1A, too much for sustained operations and no reserve for other loads.  How often do you use more than one stove burner? two small ones might work on lower settings for a short duration, but again with little or no reserve.  My little microwave pulls 11A at 120VAC, or nearly half the capacity of one of the 120VAC legs.  At least you don't have to worry about a well pump cycling on and off.  Your freezer or refer are going to pull between 1 and 2 amps @120VAC depending on their age. But since these are automated loads, you need to engineer enough reserve for them or disable them during high generator loads.  My electric dishwasher pulls around 8A @120VAC during the drying cycle

I think you will find that a dryer or water heater are out of the question on 3KW.  My dryer pulls 20.5A @240VAC and I don't think there is any way to reduce that other than configuring it for air-dry only which means long dryer runs.  A typical water heater has elements in the range of 4500 watts, mine pulls 15.9A @240VAC.  There are ways to reduce this load, at the expense of reduced water heating speed/recovery time.

If you absolutely positively have to have a dryer, you will need a single larger generator, or a small efficient average load genset(big enough for A/C, entertainment and lights) and a larger peak load genset(greater than the 5KW that the dryer requires by itself) that only runs on laundry day(and at dinner time to run the stove and oven and A/C at the same time:).  As mentioned the dryer and stove could be swapped over to gas, removeing these loads from the genset.  You could also possibly look into using the waste heat from the engine cooling system and exhaust of the smaller average load genset to warm the air for the dryer or to heat the water in the hot water tank(cogeneration).  This of course would require the heavy modification of the dryer and some plumbing and controller skills as well as a greater capital investment in the heat exchangers to reclaim the waste heat.  But you payed for the fuel, might as well get all the use out of those BTU's that you can.   Batteries/inverters are another option to store energy at off peak times to help power the peak loads.  the use of batteries, means conversions.  At the least, DC back into AC but most likley generated AC into DC to charge the batteries.  Conversions are always less than 100% efficient, sometimes significantly:(.  The batteries and inverter capable of running your peak loads would also mean another significant capital investment.

Good Luck.