I've been a Makita guy for many years, and am still heavily invested in them (lxt18), but some Milwaukee m18 and m12 has started to creep into my shop, and more will come (still keeping makita's though). I prefer the Makita battery latch style though, as they're much easier to release one handed for me. For my needs, either are fine, but there's a reason M18 Fuel tools are the so prevalent on jobsites. They're just tough, hard working tools that stand up to abuse better than the rest. Almost all brands would suffice for most home handyman and tradesman use though.
If you're already in the M18 ecosystem, then stick with it. Upgrade to some 5ah batteries at least a little at a time. They really do add that extra bit of longevity and umph to make cordless tools that much more usefull, but they're expensive. MUCH cheaper to get some with a package on sale, and either sell the other tools and keep the batteries, or find tool packages you want. Don't buy any new tools that aren't brushless, and look for the Fuel version of the tool instead of normal, they're just higher quality.
That 1/4" hex drive impact you have is pretty handy. I have a couple Makita ones, and love them for driving screws and also with 1/4" drive sockets. Get some 1/4" hex to square drive adapters (
on sale now at princess auto) to make it even more useful. Then buy a 3/8" square drive stubby impact, and after that a BIG 3/4" for the big stuff (you can always adapter down to 1/2 if needed.) If you're working on vehicles and heavy equipment that's how I'd go. A 3/8" fuel ratchet would be handy to pickup cheap used, and A battery grinder is always awesome too. I love mine and want a few more. Home depot has 5" m18 grinders on right now for $98, same with
KMS tools. I'll probably pick one up today or tomorrow from KMS when I get a chance to browse what else I "need" to make up the extra $1 to get free shipping.....$100 is a great deal. Not a fuel version though, but for my needs at home it should be fine.
KMS tools, and
Atlas Tools are pretty good for cheap package deals every once in a while. It's a great way to upgrade your batteries for dirt cheap if you sell the tools afterwards. Don't forget yard tools either. I love my Makita string trimmer and blower. The combo was also a cheap way to get another 2 5ah batteries too.
Things like
this deal are a fantastic way to get your foot in the door. Almost considering buying it to get the 1/2" drive impact, or another battery grinder and upgrading my drill and 1/4" impact to brushless versions as well as two more 5ah batteries......Very tempting.