The form factors for the current iPad Mini and the base iPad are fine for the entry level market. iPad Mini needs a spec bump and Apple Pencil support right away. They could give the base iPad a refresh to A11 or A12 later in the year, maybe when the A13 chip is released with new devices in the Fall. Apple does not need a special media event for a refresh.
Touch ID is fine for most folks, and frankly, the bezels are handy. Most iPad users don't give a rip about promotion or laminated displays. They don't need quad speakers on their iPads, and they prefer to have a headphone jack. The A12Bionic is way more powerful than necessary for the most frequently used Apps.
It is really important that Apple keep these iPads affordable.....$329 is the sweat spot for the base iPad. Also, I would like to see Apple reduce the price of Apple Pencil 1 to $79.