Well, you're always going to get nearly as many opinions as people replying, so here's mine
Small holding is about following your heart.
You like the idea of calves in spring so - go for it - get a couple of in calf cows.
Dexters are convenient to start with because of their reduced size. If you get short legged ones you can even use sheep hurdles to gather them. And if, like Buffy, you have a lamb creep, them they will be able to test it to destuction. (Did it last a week?
)
But DOensure they are quiet and well handled. I once got 2 that were very cheap and very difficult to catch, and I thought I could handle them once they got home; but they turned out to be dangerous. I couldn't let my kids in the field with them because they would seriously go for them. I didn't keep them long but put them straight into market and even there, one turned on one of the drovers
However, that really is the exception, and I've no idea what had made them like that.
My first dexters came from a retired neighbour who kept them as a hobby. They were all halter trained
and would happily eat out your hand and stand to be petted and brushed. They do tend to have "small person syndrome", and my quietest, show winning one would still never miss the opportunity to try and crush me against the side of the trailer when I led her in, but she didn't have enough weight to even cause any serious pressure and maybe I misjudged her and she just liked being close to me.
So - have a look at the ones for sale locally and just see what they are like when you walk amongst them in the field, and if possible ask to see how easy they are to gather. If they run away when you approach, then maybe give them a miss and look for something a bit more placid.