There certainly can be legitimate functional reasons/purpose for basins to be required set appropriately in relation to the wall to suit the selected wall spout setup, and having experience with similar details the spout length chosen can determine the basin position and does need to be a certain length to work properly. Sometimes this requires adjustment of basin size and bench depth. In this case something's clearly happened.....without understanding the company's particular processes my guess is that the bench depth larger than what it should be. It's your home/investment, you have to live with it long term. IMO what differentiates (great from ordinary) builders is their capacity to resolve issues and shoulder responsibility when something like this occurs. Believe me they (should) have enough fat built in the profit margins to resolve these types of issues. The good news is you actually have a physical example you can refer to in the company's display home. If required go and measure it and compare it to yours to be 100% sure - in custom/boutique situations clients don't have that luxury/back-up check. Try not to play or get drawn into a "blame" game, or accept lame excuses (which the industry is expert in ;) ), it doesn't matter exactly how it went wrong, the main thing is you want to get it right/resolved. Stick to your guns ;)

our plumber correctly installed our wall mounted spouts over the centre of the basin ie water directed to the plug hole but make sure that the basin is mounted forward of the vanity and spout is shorter rather than longer as the water can spurt forward if turned on too hard by unsuspecting guests

Bathroom renos can be daunting as there are many things to consider and usually the space can be limiting. Free standing baths are stunning and come in many shapes and sizes. You have mentioned that you and the boys will use the bath, ensure you factor in the "users" height as this will determine the bath size and depth. Firstly is the plumbing remaining in the same position? Floor mounted bath mixers can be installed with a concealed under floor box or the above floor connection method. The concealed box method is advisable before the flooring is installed, and has the benefit of a lower profile floor plate, which is preferred. The above floor method may be done where the first approach is not possible. Free standing bath mixers visually create an impact when paired with the freestanding tub, ensure you have enough room around the tub as it will be difficult to clean if it sits too close to walls and or vanities etc..many freestanding bath mixers offer functional hand showers as well as the spout, ideal for washing soap out of kids hair. Would love to see a lay out of your bathroom to assist with tap ware placement. Good luck with your bathroom renovations, always happy to assist you. Carmen Collaborative Interiors

good points SK and Eco thank you. Looks like I'll be going with the flick tap, offset at 2pm to the right of the round vessel basin, mounted in the centre of the top of the vanity (not semi-recessed). Any thoughts on whether the vessel basin should be bang in the middle, or offset to the left slightly to balance the tap being on the right?