the amount of coverage depends on your needs.
for life insurance, it's what you want your dependents to get if you are no longer able to provide for them.
a rough gauge would be to multiply your monthly expenses by 12 for at least a year's worth of contigency money.
critical illness serves pretty much the same purpose as life insurance, but the money can also be used to make yourself more comfortable (by hiring nurses etc), and by paying for the hospital bills first cos hospitalisation plans here only reimburse you.
as for hospitalisation plan, go for as charged plans for the wards that you would like to stay in. If you dont't mind paying the extra, you can always get the most ex plan, cos you can always downgrade but you can't upgrade to more ex ward for cheaper plans.