If you travel 1-2 times/year or more then yes, absolutely. The sign-up bonuses go the farthest when used for travel.
You can do plenty of research or e-mail courses on travel hacking to get more info. Basically, the sign-up bonuses can be redeemed for maximum value with travel partners (airlines, hotels).
The most flexible of these are the Chase cards because of their value their Chase Ultimate Rewards. You can book at 1.25 per point (so 50,000 points = $625 on the Chase travel portal - like an Expedia or Travelocity) BUT you can transfer these to 11 (or more now?) travel partners. So 50,000 points = 50,000 miles, which in some cases is worth $1,000+ instead of the $500 cash back.
Personally, I recommend starting with a Chase Sapphire Preferred. It has a $4k minimum spending requirement in the first 3 months and you get 50,000 points to use in Chase Ultimate Rewards. The $95 annual fee is waived in Year 1, so you could close it if your first 365 day trial period doesn't just the $95 fee for Year 2 if you want. Or you could keep it.
From there, you could keep churning through Chase cards or go with another provider. Keep in mind, you'll only get approved for a Chase card if you've opened up less than 5 cards in the last 24 months (5/24 rule). You could double up on Chase Southwest cards and get very close to the 110K points needed for the Companion Pass almost entirely through sign-up bonuses (look out for the 50K or even 60K sign-up bonuses - I believe they're 40K right now).
Another poster said they spoke to a Chase rep. who said they will be rolling out new sign-up offers in September ahead of the holidays. So keep an eye out on that. But either way, I 100% recommend the Sapphire Preferred unless you've opened a bunch of credit cards in the last two years.
