best payroll software uk for accountants handling client payrolls

Hi all I am a UK based accountant and recently took on a few small business clients. Payroll has turned into a mess with spreadsheets NI and PAYE calculations different pay dates and manual checks. I need proper payroll software that can actually support an accountant setup.

Here is what I want to know

• does any payroll system automatically calculate PAYE National Insurance net pay holiday pay overtime and statutory deductions so I am not checking every figure line by line?
• does it generate payslips for employees automatically and let me send them through email or a simple portal without extra steps?
• does it submit payroll information directly to HMRC through RTI the moment payroll is run so I do not have to do an extra filing task?
• does it allow managing multiple client payrolls from one dashboard so I am not jumping between separate accounts all day?

If you have used a system that handles these tasks smoothly I would really like to know how setup went and if it actually saved time once you were running payroll every month. Any real experience from accountants working across multiple clients would help a lot.