well seeing as the OP expressed a desire to use the chet feature i will say the GW cheat feature is pretty nifty, and if you can find a gateway card for a decent price (say around £25-35) i would say its still not a bad option, it is all self contained (no mixing and matching CFW's to keep up with the latest development) the cheat feature is pretty nifty and allows anyone to make their own codes pretty easy without having to beg for people to make NTR plugins, I did myself go to CFW's for a while as GW were falling behind by not moving with the times and taking advantage of menuhax for auto booting, but now they have embrased it im finding GW more convinient again
as for the "dlc doesnt work" stuff, basically some rom hack projects are distributed as "fake" title updates gateway doesn't work with these but most rom hack projects also have an option for HANS/CIA/.3DS repacks, the only other thing is the custom themes with CFW you can install custom themes like an official theme whereas GW for the same reason as the cia rom hacks doesn't work with these files
one more advantage of GW over CFW is the no faffing about region free, afaik no cfw's at this point have a completely reliable region free feature relying on region patched cia files and external solutions such as NTR language plugin or HANS to get some games to work properly
TL: DR if you find the GW card for a reasonable price and £25-£35 isn't the end of the world for you to spend then a gateway card is still handy to have around, but at this point its completely optional it helps streamline stuff but in doing so find itself lagging behind at times but in other aspects ahead of the crowd doing its own thing rather than snowballing anything and everything they can lay their hands on