I think you have to really love straight up espresso and a bit of spare change to blow to get any benefit from having a dedicated machine. You can create an ersatz latte with an Aeropress and a milk steamer/frother ($20-$30).
It's a deep rabbit hole if you're trying to get to same quality of shots you get in a good coffeeshop. How many beans are you willing to waste each morning while you adjust your grinder and go through a couple to several shots to get to today's ideal brewing parameters? Espresso is a constantly moving target. With each passing day beans behave differently, and it's not only oxidation, but environmental factors like how humid is your kitchen today?
That said, if you like cappuccinos or lattes and aren't all that fussy, then sure. Milk can cover up a lot of flaws in the shot. I own a Barista Express (got it for free as I worked for Breville) and it's a fine machine for that purpose. The steaming is powerful enough to get decent mircofoam. I would not get the Bambino as it's simply not stable enough on the counter. I think the Oracle line is overkill.
If I was really into espresso, I'd get a separate grinder (which you have) and something like the Rancilio Silvia, which has a big following, so lots of online advice on using it. Generally on any combo grinder/brewer, espresso or drip, the grinder will break down well before the brewer does. But then you're well over a grand for even a beginner setup.