Hey, this is the creator of I Wanna Be The Guy, here. Just had to say I absolutely love this game and have been playing it constantly for a good few months now. At this point I got a good 30+ wins under my belt and succeed at winning pretty much every time I sit down to play. The game has some fantastic polish and smart design. I have a few suggestions!
Spectacles. These things are nearly useless, which was fine until the alters got implemented (my favorite change, BTW). The difference between getting spectacles(most useless non carry-abe in the game)and getting climbing gloves (the all around best item in the game when you factor in the jetpacks rarity) is huge. If spectacles are going to be the default alter drop, they should at least have a tad more functionality. The first thing that game to mind is allow it to see crated items. Another possibility is letting you look up and down farther. A 3rd possibility is for them to act like a weak light source (So not as good as the hedjet).
I think even if it had all 3 of these functions, I'd rather have climbing gloves. But at least I wouldn't feel like I missed out too badly.
The machete also needs a lift, but I think everyone knows this. I think even greater range might be beneficial, but the real change I'd like is to have it be an upgrade for the whip. I think it'd be kind of neat if bombs, rope and your weapon had an upgrade, but this might be too drastic a change.
As for the alter, it's great, but the payout method seems poor. In early levels, unless I see a kissing booth to massacre, the alter isn't worth much. I'll be lucky if theres a cave man -- and for what, a pair of spectacles?
Heres my thought... Lets say you sacrifice a caveman. Well, a bag of bombs appears on the alter and the bombs behave like a shop. Lets say, next you put a damsel down. The bombs on the alter turn into spectacles -- from here you can continue up the item chain and if you leave without taking the item, the item will appear at future alters.
Edit: Oh, i'd also be nice if arrow traps indicated if they were trigger. I wouldn't ask, but I am sick of getting hit by arrow traps that didn't go off when I threw something past them.
Another simpler alteration I think would just have the alter spawn items more than once (maybe alternate between that and invigorate?). I wouldn't mind missing out on 99 bombs. It's sort of too good and totally demolishing the golden city is getting a tad boring.
Anyways, this game is still one of my favorite games ever and I look forward when the source code is released and someone makes NetSpelhacky.