The problem with nothing is it often appears not to be nothing upon examination, and its hard to be sure about its real shape. We don't really know what 'space' actually is except that it is definitely malleable The other problem is that all we see is the Observable Universe, a sphere of which we are the physical center, essentially a geocentric model of the universe where the very edge is 47 billion light years away from Earth and 13 Billion years back in time. That's not the Universe though, anymore than a balloon is a house, we don't know the houses shapes and can't assume the balloon being a sphere makes the house a sphere, but it probably is. We don't know the size of the true Universe, some theories indicate it's not much bigger then the observable, some that it is many trillions of times bigger, that our 93 Gly diameter sphere is just a pebble on the beach, and it still has not been ruled out as infinite in size. Or even Age, our Big Bang could be a 'local' event, we haven't totally ruled that out though we tend to say so. The observable Universe can't have anything in it older than the 13.7 Gy and we'd have to have space around us a decent bit bigger that was cleared so no older light had reached us yet, which seems fairly improbable. So we could be shaped exactly as you suggest, and on a spike, and just 47+ GLy from the 'skin', or less, 47 GLy is how far those objects are now not when we saw them. sort of like the Quasars, there are very few 'near' us because most if not all of them have shut down, with Hanny's Voorwerp 700 Million Light years away probably one of the last and it shut down recently, about 70,000 years ago, or 70,000 years plus 700 Million years. It's entirely probable there are no quasars left in the Universe anymore.

But back to what you were saying, obviously there's no particular proof the Universe is or isn't shaped like a ball with needles on it but the Observable Universe is a sphere. Outside the Observable Universe, or Hubble Volume, we know nothing. Occam's Razor says more of the same out to infinity or very large, if very large but not infinite we get into that 'what is outside the Universe?' conversation which nobody has any answers on much more sophisticated then what people thought was outside the Firmament. We do know that it requires a volume of 10^188 meters radius, or 10^172 light years before it wouldn't matter, because that's the 'repetition volume', or that area of Uniqueness in which if the Universe were infinite that's about how big a volume you'd need to search to find to effectively identical things, the flip side of how many times you need to shuffle a deck of cards before you'd expect it return to its original configuration, how many decks of cards you'd need to look at to find two which were in the same order. We are reasonable confident, from Dark Flow if nothing else, that there's more beyond the Observable Universe, but we really don't know jack about Beyond or Before.