As my add to this conversation, I've never fished or relic hunted for more than 2 times in a row!
However, I've once started fishing and I really liked it and said to myself, I'll fish about 100 points everyday, untill I hit the 50 points limit.
I didn't like this, at all.
I do agree there should be a limit, because gaining points like this is really easy. However, 50, is still a bit low.
Therefor I agree with increasing the limit to at least 100.
Based on other people their opinion, most say you should play minigames. Which I can agree to, these give way more and way faster a good amount of points. However not everyone likes this, nor is good at this.
The Fishing and Relic-Hunter game are a good replacement. There's a 50 limit, come on guys, why not increase this? You can get way more if you win every game, like WAAAY more. So I do not see the use of only giving it a 50 limit.
tl;dr: Other games get you way more points and exp, so the low limit isn't that "limiting" to get points because other games will just give the remaining points. Increasing the limit is a good idea!