I am not getting the 2nd point.
Can you describe it further or give me the url and let me know how to reproduce it?
There are 2 specific issues here I think.
First, understand that there is a parent product that is generally not orderable in a clothes store. The children of that product are the orderable variants of the product.
So, with regard to maintaining stock, how many t-shirts (for example) that you have is not useful or relevant either to the customer or the supplier.
What is relevant is how many Red t-shirts in small, how many green t-shirts in medium and how many blue in x-large. You might have 30 t-shirts left in stock, but only in those colour and size combinations.
So, if the parent product has zero stock, the product is displayed as out of stock, despite the fact you have 30 t-shirts available.
If the parent product is set to a stock of 1, then it is then shown as 'in-stock'. But, if someone wants x-large t-shirt in Red, it is not in stock.
Therefore, the display of the parent product SHOULD show if there are any child products in stock, i.e. the sum of all child products, and its own stock is not relevant. This is probably a template issue rather than a plug-in issue, but I do not profess to know where it is best implemented.
Here's an example
http://elanvape.com/index.php/en/shop/liquids/eve-guava-e-liquid-detailthe parent product says 1 available and prompts to choose a variant
You can choose between strength at 0, 6 or 12 and size between 5 and 15
There are a total of 15 available, 5 of each