Hi and welcome to the GMB

don't worry about making mistakes, we all have to start somewhere.
first comment would be that when we speak of a 'pontil' we are referring to the pontil rod - this is the metal rod attached to the underside of the foot to allow some final work on the glass, for example fire polishing the rim. When this is snapped away from the glass, it leaves a sharp scar, which nowadays is ground/polished, thus leaving a circular depression - an indication, usually, of a quality item, but it is on the underneath of the foot, not between bowl and foot.
The underside of your glasses are probably quite smooth, I suspect.
Any lumps/bumps etc. which are found between bowl and foot, are usually decribed as knops - those round things found more often on very old drinking glasses.
Know what you mean by 'hobnails', but regret to say (as a lot of your countrymen will tell us) that a hobnail is something quite different. They occur on both pressed and cut glass, and are usually a six sided piece of decoration that is formed as a result of three sets of parallel lines - a diamond if you like, with six sides. Some more intricate hobnails have eight sides.
The fact that you can't see any mould seams doesn't mean these glasses aren't press moulded - glassmakers are clever when it comes to fire polishing, and seams can be removed.
I'd suggest these pieces are produced by moulding in some way - which is how your 'hobnails' have been created.
Colour wise, it's often the case that less lead makes for yellow tints, and an increase in lead gives a slightly greyer tone - if you flick these they will probably give a very short dull sound - unlike lead glass which will ring for some seconds.
Can't really help with age, other than to say most probably post 1950. It's a common mistake that people make to think that because their glasses have come from a great aunt then some equally great age is involved.......memory plays tricks and our possessions are often not as old as we'd like them to be.

As to use, I'm really not sure, but might suggest for lemonade or water.
Hope you won't be offended by these rather basic comments, and hopefully someone from your side of the pond will be able to give more useful information - and thanks for posting by the way.