It's fine, and it's also a good practice because you save an useless vias, so pads and holes that in addition would have to be made conductive, with a wire or with a metal fill.
So when you design your circuit, besides trying to use in the wisest way your two layers, try to use as much as possible the holes for the pins of the components, to pass traces from one layer to the other.
Plus, if the design is complicated, you can get a hint from the Manhattan tecnique, that is trying to split the traces in vertical and horizontal, and use one layer for one type and the other for the other one, as much as possible...so you have the less chance to have crossing lines in one layer.
The counterpart is that in that case you have to solder also the upper pad of the board; if you pay attention, there's no problem but you have to be more careful to avoid damaging the component. And also, if you find a mistake, the desoldering process becomes more complicated too.