It is common knowledge that the traditional system for counting High Card Points (HCP) is flawed. Ace=4, King-3, Queen=2 and Jack=1 overvalues jacks while undervaluing aces and kings.
More accurate is something like:
A=4 1/2
K=3 1/3
Q=2
J=3/4
I don't recommend using those fractions, but is is good to be aware of. All these fractions would give most people a headache.
I'd like to propose a simple solution.
When your hand is heavy with aces/kings (as opposed to having lots of jacks), just take a slightly optimistic view if you need to. For example, if you are thinking of going on, do so. After 1-3, go to 4 with:
A10876
A2
A432
54
but, pass with:
QJ542
Q2
KJ32
KJ.
The 4-3-2-1 system also doesn't account for 10's and 9's.
Some teachers espouse counting 10's as 1/2 and 9's as 1/4. Again, I hesitate to make a player calculate fractions.
Regarding 10's, not all of them are useful. The 10 in each layout below is worthless:
10xx opposite Jxx
10x opposite Axx
10xxx opposite xx
In the following layouts, the 10 is potentially useful:
J10x opposite Qxx
Q10x opposite Kxx
A10x opposite J9x.
Granted, I chose the examples carefully, but what do you notice? In the first group, the 10 is accompanied by only small cards. In the second batch, the 10 is accompanied by a higher honor.
In general, a 10 with a higher honor is quite valuable. Accordingly I propose the following guideline:
Add 1/2 point for a 10 if it is accompanied by a higher honor.
True, this is not an exact science. But, I recommend giving it a try to see if your bidding evaluation improves.