First of all welcome to EK
And about your question it depends on whether u are ready to do some extra hard work. It's just the situation of our country, it's very competitive so even we work hard we may not be able to qualify for local universities maybe by a few marks, also there is a quota system. (so if u'r in colombo u may get 3 As and no access to uni while a person from a rural area with 1B 2C can get the seat

)
You need to plan your future clearly before getting u'r self in. Think if u don't get local uni access, are u ready to apply for a foreign uni (are u able to get the required qualifications, are u able to afford the cost etc)
My situation . . .I did ALs in bio stream . . . was unable to qualify for local uni first try . . I did second try and meanwhile a IT course too . . .again was unable to qualify . . .so after finishing my IT course I came to China to study medicine . . my plan is to complete the degree here and continue PG in some other country (preferably europe or aus)
IMO u should work hard in the stream u select . . and put your maximum effort to qualify to local uni. If u'r unable to qualify . . don't waste your time for second try . . pack up and go abroad
When ppl ask me about stuff . . now I normally say complete your OLs then select the field u like and study abroad . . 2 years for AL is a waste of time. eg: a prospective med student after OLs can do premed(1year) and apply for a medical uni. see 1 year is saved . . . a prospective commerce student can do CIMA foundation and then continue abroad . . no need of ALs
This is all my opinion . .u have the right to choose u'r self . .think carefully and decide, don't make u'rself to regret later . . good luck.
