Wow, your complaining about buses only running every 20 minutes in the evening and on Sundays…!
The biggest problem is having to catch two of them in Portsmouth to travel only 1.6 miles, 1 mile on the No.1 bus and the 0.6 miles on the No.25. So the amount of time spent standing round for the two buses to arrive and very long interchange between the 1 and the 25 (to only travel 0.6 miles more) means at best you save only about 10 minutes compared to just walking the whole 2.1 miles.
My local rural bus 93 in Capel is only hourly but is reliable time wise and on Sunday when no trains are running from Dorking to Horsham its the only realistic way to do the 6.5 miles to Horsham or 7.5 miles to Dorking without a car. But it is is extremely expensive and costs £7.90 return for a 14 mile round trip or £4.90 for a single and Yet Metrobus's Metrovoyager ticket that allows totally unlimited travel all over their network all day is only £8. And A Discovery ticket that lets you travel on all bus routes across the whole South East of England outside London on multiple bus companies is only £9 for a whole day's travel (which could be well over 10 hours worth). But the Dorking and Horsham Plusbus schemes don't cover the 93 route 7 miles south of Dorking and 6 miles north of Horsham to where I live in Capel but only for about 2.5 miles around each town.
The relatively shorter distance (but not as short as my 1.6 miles journey on the No.1 and No.25 combined in Portsmouth that I end up concluding every time I buy Plusbus and catch them that I am better off avoiding and saving the £2 Plusbus fare and walking instead) fares on Metrobus for the route 93 are simply far too expensive in relation to the only hourly service and the appalling crashing, banging and thumping ride quality of the clapped out but totally unnamed manufacturer (one bus driver suggests they were made by Dennis) buses used. And I only need to travel on the 93 at all on a Sunday when Southern gets away with running no trains from Dorking to Horsham all day long.