If you have done a PPL in minimum hours I wouldn't be too concerned about aptitude tests. As you already hold a PPL sticking to the more flexible modular route gives you lots of options. Take each stage as it comes, only if you have constant & persistent problems (there will be some setbacks) would I reconsider your plans. At least you have had a backup plan in finance should the need arise. Once you hold a Frozen ATPL most airlines are unlikely to ask you to do a basic aptitude test they are more interested in your flying & MCC skills along with sim check rides, there are several companies out there providing assistance for this.
Don't forget airlines recruit on a supply/demand basis & their requirements can change up or down very quickly, it will be another year at least before you are in this position, best of luck.